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You know that thing where an orchestra swaps instruments, and like, some of them get it right away, but others have no clue what they're doing? This is that but with quirks, two unwilling participants, and also Emotions

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Momo liked to think she was on fairly good terms with all her classmates. She might not be close to all of them, and she certainly knew some better than others, but she didn’t have any enemies. Not since Mineta was finally expelled. When they were assigned group projects or team-ups, she was able to work with anyone happily. It was rare she got into a serious argument with anyone, and they were usually resolved without any hard feelings.


Yes, Momo felt comfortable saying she got along well with her classmates.


Or, well, she felt comfortable saying she got along well with almost all her classmates.


It wasn’t that she and Katsuki were on bad terms, if anything he was more respectful to her than he was most of the class. But Katsuki was a difficult puzzle at the best of times. Between his prickly exterior, aloof nature, and… unique way of showing affection, figuring out how he felt about anyone was a guessing game. They weren’t enemies, but she wasn’t sure if she could call them friends either. Even ‘close acquaintances’ felt like a stretch at times.  


Still, whatever their relationship, it was good enough that the two of them were standing side by side in front of a fascinating exhibit on the chemical makeup of quirk factors. Their entire class was scattered around the recently opened National Quirk Sciences Museum, a relaxing field trip before they plunged into the chaos of studying for finals. At some point Katsuki must’ve gotten away from his usual group, since none of them were in the room.


Neither of them had spoken yet, and Momo had spent the last ten minutes debating if she should. Katsuki did seem to be enjoying the silence. Maybe? It was always hard to tell with him. 


She finally made up her mind, opening her mouth to ask his opinion on the hypothesis for quirk factor strength determination, only to be cut off by a BANG from across the room. 


The far wall had exploded, in it’s ruins stood two men, one decked out in blue and the other sporting a particularly ugly green outfit. 


“Fuckin’ villains, can’t give us one goddamn day off.”


Momo sighed and nodded in agreement with Katsuki’s annoyed growl as the two of them jumped forward. Neither of the villains looked familiar to her. 


“Do you recognize either of them?” 


“Nope, probably two-bit thugs lookin’ for attention.”


She gave another nod and surveyed the battlefield. There had only been a handful of other people in the room, all thankfully well away from the wall and currently clearing out. The blue villain had some sort of spikes on his body, while the green one was tall and bulky with a horn indicating some sort of strength quirk. 


Sharing a quick glance with Katsuki, they came to an unspoken agreement. She reached down to her leg to pull out a staff, range fighting would be key. Katsuki tensed himself, and she was ready to leap into battle when suddenly there was a hand on her arm and a tingle traveling up her spine.




Apparently, there was a third villain. He’d snuck up on the two of them to latch onto her and Katsuki. Whatever his quirk was, it didn’t stop Momo from grabbing his arm and flipping him over her shoulder, throwing him across the room towards the other villains. Katsuki jumped after him, ready to take advantage of the opening, and Momo braced herself for the loud explosion that was sure to follow that manic battle grin.


No explosion came. 


Something was wrong. Momo didn’t have time to consider it because the blue clad villain was leaping forward to try and take advantage of Katsuki’s moment of vulnerability. Lashing out with her staff she knocked the man off balance so the two of them could fall back, regroup and get their bearings. She reached for her quirk, hoping to create a smoke bomb, only to find herself unable to activate it. 


The two heroes in training made eye contact, both looking surprised. This was bad. 


“We need-” Katsuki shouted, only to freeze mid-sentence. One of his hands flew to his ear as if he’d heard something, but Momo didn’t know what. She opened her mouth to shout a reply, but no sound came out. Before she could try again, the green villain rushed in, missing her by a hair. Well, it was a damn good thing they were trained for hand to hand combat. 


Using her pole, Momo leapt at her opponent, flipping over him to deliver a sharp blow to his side which knocked him to the ground with a pained shout. For all his bulk, he wasn't particularly hardy. 


Katsuki recovered from his own shock and engaged the blue villain, dodging around his spines to deliver painful looking blows. The villain who’d disabled their quirks was still down. Good. This should be over soon enough. 


Wiping her brow, Momo concentrated on her own fight. Slamming her weight down onto the villain’s leg, she whacked his head with her staff, hoping it would be enough to take him out. 


Unfortunately, not quite. He reared back, knocking her off balance. Her hands flew out to her side to steady herself. It would've helped if not for the twin explosions from both her palms. 


The explosions were weak, but the distraction let the villain throw her off. Momo tried to bounce back to her feet, only to again be thrown off by twin explosions. They were getting stronger. The green villain rounded on her, and well, no time like the present to learn something new. Bracing her back against the wall and aiming both hands at her opponent, Momo concentrated on that explosive feeling. 


What shocked her most wasn’t the power of the explosion that followed, it was the silence of it. The blast knocked the green villain into the opposing wall, his body sliding down it to collapse into an unconscious heap. She’d fought around Katsuki often enough to know how loud his explosions were, and she could feel the vibration of the blast reverberating in her body, but no sound reached her ears. 


She had no time to consider it further though, because now the explosions had started coming, they seemed uninterested in stopping. Sparks and little pops came from her palms, growing in size and strength, and Momo didn’t have the faintest idea what to do about them.


Katsuki took one look at her and his face twisted. He was caught up in fighting the final villain. Still, he leapt back long enough to point towards the door. 


“Go! Now! Find someplace empty and quiet!” 


Normally, Momo would never run from a fight, but Katsuki had a near panicked glint to his eyes. He looked more worried than she’d ever seen him before, and that was enough to convince her. Turning on her heel, she vaulted the rubble to escape from the room, pausing for a moment at the entryway to hear him shout one last time. 


“And for fuck’s sake, don’t touch anything !” 




This wing of the museum was devoid of people, but she didn’t want to risk causing structural damage by staying inside. After pausing to catch her breath, Momo was able to concentrate enough to mostly stop the explosions coming from her hands. They were still covered in sweat though, and she didn’t think she could keep them at bay for long. Best to get outside quickly then. 


Pulling up a mental map, Momo navigated towards the closest fire exit. If nothing else, she’d be able to escape easil-


“Is someone up there?”


The small voice startled her, causing another round of explosions. Damn it. Still, she called back. 


“Yes! I’m here, where are you?” 


Again, her voice didn’t make a sound. At least, not to her own ears. The words vibrated in her throat before seemingly vanishing into the air. She must’ve said something though, because the voice responded. 


“In the pit! Please help!” 


Scanning the room Momo spotted the pit, part of an exhibit, and darted over to it. It was ten feet deep and probably fifteen feet in diameter with no ladders or exits beyond a staff-only door in the back. In it there were two children, siblings maybe? The bigger of the two was a girl that looked about five, while the younger was a black haired boy that couldn’t have been older than three. The boy was curled up on the ground, eyes watering and arms wrapped tightly around his chest.


The little girl spotted Momo peering over the edge and her face brightened up. 


“Are you a hero? Can you get us out of here? I tried to climb, but it’s too high up and my brother hurt his leg.”


Momo gave the girl her best smile, trying to keep her hands from exploding. Speaking without hearing herself was hard, but she adapted to the struggle quickly enough. 


“I am! Don’t worry, I’ll get you out, I’ve just got to-” Cutting herself off, Momo realized she didn’t know what she was going to do. 


If she had her regular quirk she could’ve just made a rope and used that to climb down to the children. Even without her quirk, it was only ten feet, she could’ve scaled the wall. But right now her hands were coated in nitroglycerin, if she set it off by accident then it’d knock her away from the wall and scare the kids. Glancing back down, the girl looked worried. 


“Ah- sorry. Just give me a moment. I’m ah- dealing with a new situation right now.” 


“Did the villains hurt you? Are you gonna die?”


“Oh, no, nothing like that. They just… made things complicated. Everything will be okay, just wait there, okay?”


Nodding, the girl still looked unsure. Momo frantically searched her surroundings for anything she could use. Nothing stood out to her, leaving her with only one choice. Jump for it. Swinging herself over the fencing around the pit, Momo plotted her landing, carefully.


“Alright, I’m going to jump down there to help the two of you. Can you stay right where you are? There might also be a loud noise from my hands, but it won’t hurt you.”


Again the girl nodded, eyes wide but trusting. With a deep breath, Momo braced herself and jumped. 


Her feet hit the ground and she rolled, only slightly thrown off by the miniature explosions from her hands this time. She’d have some bruises in the morning, but nothing broke. Pushing herself back to her feet, Momo turned to check on the two children. The little boy was shaking, while his sister seemed startled. After a second, the little girl recovered and raced over to Momo’s side.


“Thank you! Can you carry my brother? I don’t think he can walk and I’m not strong enough yet!”


The ‘of course’ formed on her lips before Momo realized the flaw in her plan. Right. There was an extremely volatile substance dripping from her fingers right now. Not only that, but nitroglycerin was toxic too, wasn’t it? She couldn’t risk touching either child with her hands. 


Momo found herself hit with a wave of respect for Katsuki, she had no idea how he managed to deal with all of this, let alone so effortlessly. Some part of her wondered if this was why he hated rescue work. 


No time to think about that now though. The battle was still going on, which meant she needed to get these two out of here. Looking down towards the girl by her side, Momo again gave her her best smile.


“Of course I can, I just need to open that door first so we can leave.” 


It was locked, because nothing could ever be that easy for her. There was no way she could climb out of the enclosure, but her mind helpfully supplied a rather clever trick she’d seen Katsuki use. Pressing the palm of one hand to the door’s lock, Momo concentrated, trying to create as soft a blast as possible.


The resulting explosion knocked the door off its hinges. 


Oh well, even though it was a bit excessive, it did the trick. That stunt also burned most of the nitroglycerin off her hands, though she was sure that wouldn’t last long. Shrugging her jacket off her shoulders, Momo hurried over to the boy on the ground. His brown eyes were dripping tears, and he flinched when she crouched down next to him. 


Momo had to fight to keep a friendly smile on her face, even as the boy watched her fearfully. It was the first time she’d had a child look at her like that, and even though she understood why, it still stung a little bit. No point in dwelling on it. Pulling off her jacket, Momo spoke as cheerfully as she could. 


“May I pick you up? I’ll be very careful.” 


The boy watched her for several long seconds, looking to his sister who gave him an encouraging nod. 


“Do you promise not ta’ ‘xplode me?”


Fear colored his soft voice, and Momo almost flinched back from it. Her smile almost hurt from how forced it was. 


“I promise! I only explode bad things, like villains and locked doors.” 


After a few seconds longer of painful consideration, the boy gave a jerky nod and Momo moved to carefully scoop him up, using her jacket as a protective barrier. It was hard to adjust him without being able to use her hands directly, but she managed. 


Once she had the boy in her grasp, she slowly stood back up, being extra careful to not jolt his injured leg. Usually, she’d want to check for a break first, but she’d need to be able to touch him to do that. Turning to his sister who seemed a little more comfortable, she gave a bright smile and put on her best cheerful tone.


“Come on, let’s go find everyone else!” 


With a nod, the girl followed her and they made their way out of the pit into the service hallway. These hallways hadn’t been on the visitors maps, but Momo figured out the way with a bit of thought and lead their little group out towards where the front of the museum should be. The silence over them was heavy, so she tried to break it. Talking felt odd without being able to hear herself, but it was better than the nervous quiet.


“How’d you two end up falling in that pit?” 


It was the girl who answered her, with a roll of her eyes. 


“I was walking him back to mama when there was a really loud scary noise. He startled and ran without looking, so he fell in. I didn’t want to leave him down there all alone, so I slide down the wall. Only, once I was down there I couldn’t get back up, and everyone else was already gone.”


She paused, thinking something over for a few seconds. 


“Did you make the loud scary noise?” 


The question was innocently curious, not accusatory. It still stung deep in her chest. 


“No, that was a group of villains.” Both children tense up, the girl looking around quickly as if she thought villains would appear any second. Quickly, Momo reassured them. “It’s okay! My classmate and I are both heroes in training, so we took care of it. He was finishing up with the last one when I had to leave.” 


“Why’d you have to leave? Is it ‘cause your hands started ‘xploding? Do they not do that normally? Do you think your classmate is okay?” 


“Yes, it was because of my hands. They don’t do this normally, but it’ll be okay. It just meant that I couldn’t help in the fight. My classmate is really strong so I’m sure he’s fine. Our other classmates and teachers are here too, and they’ll help him if something goes wrong.” 


The girl looked like she had more questions. Said questions were stopped in their tracks when Momo pushed open a fire door letting them out into the sunlight at long last. They’d emerged outside the front of the museum, where there were thankfully paramedics already on scene. Several of her classmates were helping keep the general public at bay, while others appeared to be heading back into the museum. Mina spotted the three of them first, racing over and nearly startling Momo. 


“Momo! You’re okay, we hadn’t heard anything so-”


“Mina, I can’t explain, but I need you to take this boy and get him to the paramedics right now. His leg is injured.”


She hated to interrupt her friend. The sweat she could feel building up on her hands took priority though, her jacket wasn’t going to work for much longer. 


Mina’s eyes went wide, but she obeyed without question. The boy was scooped up into her arms and she raced over to one of the waiting ambulances, easily making her way through the crowd. Momo let out a sigh of relief, before turning her attention to his older sister who was looking up at her for instructions.


“You should follow her, they can help you two find your mama, okay?” 


The little girl gave her a nod and a smile, eyes shining up at her.


“Thank you Miss Hero! I hope your hands stop exploding soon!” 


And with that she turned to race after her brother. Kyouka and Tsuyu had been making their way over to see what was going on, only to freeze when they processed the child’s words. The gathered crowd had overheard too, and whispers were starting. So much for handling this quietly. Momo could already feel a headache coming on as tension settled in her body. 


Before Momo could explain, a flash from her palm did it for her. Only instead of a small explosion, the built up sweat collected on her jacket ignited, causing a blast that almost knocked her off her feet. 


Damn it, that had been one of her favorite jackets.


Nothing to be done about it now though, as it’s ashes fluttered to the ground. All eyes were on her and she realized she couldn’t stay here. What had Katsuki said? Someplace quiet and empty? The museum had a small outdoor garden that should’ve been evacuated. 


Kyouka took a nervous step towards her, looking unsure and scared. 


“Momo- are you?”


“I’m fine! It’s- one of the villains had some sort of quirk swap ability and he caught Katsuki and I!” 


Her friend’s eyes went wide with realization as she flinched back. Momo might’ve said that a bit louder than she meant to. The crowd latched onto that information too, murmurs getting louder and faster. She could feel another explosion in her palms. If she didn’t get out of here now, everything was going to get worse.


“I’ll be in the garden, don’t let anyone follow me unless it’s Katsuki or Aizawa-sensei, okay?”


Kyouka nodded, and that was all the confirmation Momo needed before she turned on her heel and booked it around the building. Once she was out of sight, the little explosions started again, and she barely made it into the safety of the hedgerows before crackles escalated.


Once she was relatively safe, the adrenaline started wearing off and Momo realized her hands ached. Looking down through the popping explosions, her palms were covered in blisters. Each new explosion brought a flash of pain with it, and each flash of pain triggered another explosion, growing ever stronger in a vicious cycle as panic surged to claw at her throat. Squeezing her eyes shut she tried to block out the pain, tried to take deep breaths and keep herself calm, but it was getting harder and harder with each passing second. 


After one particularly strong blast almost took her off her feet. Momo dropped to the ground, holding her hands as far out from herself as she could to reduce the damage. Tightening her shoulders, she could feel the explosion building in her core and knew it was going to hurt. Mentally she counted down, trying to find any comfort in this hellish experience. Three. Two. O-


The feeling vanished, replaced by pins and needles. Her eyes snapped open to the very welcome sight of her teacher’s crackling red gaze. Just as welcome was the blonde next to him, who looked a little scuffed up but no worse for wear. Katsuki’s face was still twisted up, a tired anxiety shining in his narrowed eyes and the sharp teeth dug into his lip. 


Letting out a sigh, he shrugged his backpack off and pulled out gloves, a bottle, and a cloth After glancing at her hands, he reached back to grab a first aid kit as well. Without pausing, he tugged on the gloves, strode to her side, dropped down beside her, and snagged her wrist to inspect her palms. It was hard to make out any specific emotion on his face as he looked over them before turning to grab the bottle and cloth. Annoyance and exhaustion, maybe. 


“The kids you saved, the girl said you used your jacket to pick the boy up, but did any of it soak through?” 


Momo shook her head. She’d been careful. 


“Alright, good.” Katsuki wet the cloth with the substance and turned back to her. “Fair warning, this is going to hurt like hell.” 


Gritting her teeth, Momo nodded and braced herself for the pain. 


He was right, whatever was on that cloth burned her skin like hellfire. It took everything she had to not pull away. He worked quickly, but it felt like an eternity before he finally finished and released her hands. Aizawa dropped his quirk, huffing out a sigh as Katsuki turned to the first aid kit. From it he produced a cool cream which felt like heaven to her charred palms. 


“It sucks, but that shit’s the only stuff that’ll get the nitroglycerin off. Water doesn’t work, so it’s that or burn it off properly. It doesn’t last forever, but it’ll buy you about ten minutes .” Katsuki spoke more quietly than usual, clinical about the whole situation. His gaze turned to Aizawa. “Any updates on how long we’re gonna be stuck like this?” 


Their teacher checked his phone and shook his head. 


“Nothing yet, run under the assumption that it's going to be awhile.”


With a grime nod, Katsuki looked back at her. The silent apology in his eyes made it pretty damn clear this was going to suck. 


“Right. Basic shit first, you’ve got nitroglycerin coming out of your hands. Sorta. It’s actually a mixture of sweat and nitroglycerin, but it behaves the same as regular nitro. Don’t touch shit unless you’re prepared to blow it up or you’re damn sure your hands are clean. Don’t touch people unless you’re absolutely sure your hands are clean. You need to learn how to ignite all of it at once to clean off your hands, there’s no other good way to get rid of it.”


He inspected her hands for a few seconds, taking in the blisters. 


“It’s gonna hurt like hell until your hands build up enough skin to take the blasts, no way around that part. Your muscles are going to ache from the ignition, and until you get controlling the recoil down, odds are you’re going to be getting knocked around a fuckton.”


Momo found her voice at last, letting out her own sigh. 


“Well, it sounds like this will be an extremely pleasant experience.” 


She got a bitter grin as Katsuki finished up with the cream. 


“Yeah, I’ll be honest with you Ponytail, this is going to fucking suck. Only good thing is it happened to you and not like, Denki, or god forbid, Deku. At least you knew not to touch the kids with this shit on you, half the idiots in our class would’a gotten themselves or someone else killed by now.” 


Several seconds ticked by while Momo processed Katsuki’s words. She had to replay them in her head several times to recognize the veiled praise. Despite the ache in her hands, she couldn’t help but give him a weary smile in response. 


“I suppose that’s something to take comfort in.” 


Another few seconds of silence in which they all took a moment to breathe, broken by Momo as she turned her mind to the near future. 


“... How am I going to ride on the bus back?”


Katsuki bit his lip, eyes narrowing down to a glare, though it seemed to be directed towards the universe in general rather than at her.


“Lucky you, today’s the one fucking day I forgot to bring my gloves with me, and they’re probably not going to fit you any-”


He stopped mid sentence, an epiphany coming over him.


“What the fuck am I talking about, that is literally the one fucking problem I can solve easily. Hang on, lemme see your hands again.” 


Without waiting for her to reply he grabbed her hands, flipping them over a few times before releasing her to yank up his own shirt. It took him a moment of concentration, then a familiar glow spread on his skin and out came a pair of gloves. They looked just like the ones Katsuki wore on his hero costume, only this pair was red and white instead of his signature orange and green. 


Snagging the gloves, Katsuki held them out for her to take, which she did after a second or two of shock. 


“Thank you.” She said, not only for the gloves, but for everything he’d done for her. There was more she wanted to say, words of gratitude and curiosity in her throat. Katsuki had other plans though, pushing himself to his feet to gather his supplies and return them to his backpack. 


“Come on, we gotta get going. The gloves help, but they don’t work forever.” 


Aizawa waited until she’d pushed herself off the ground, matching her pace as the two of them trailed behind Katsuki back towards the others.


“You alright kid?” 


It took her a few seconds, but Momo gave an uneasy nod. 


“It’s- It’s a lot, but I’m okay.” Then after a few more seconds, she added, “I had no idea that Katsuki’s quirk was so-” Painful. Dangerous. Complicated. Limiting. Hard to control. Volatile. “- much .” 


“That makes two of us.” Glancing up at her teacher, Momo could see the worry in his eyes. Directed both at her, and at the explosive hero ahead of them. 


They reached the front of the building in no time at all. Most of the crowd was gone, only a few police officers were still hanging around. The rest of their class was waiting anxiously by their school bus, gathered around Mic-sensei who perked up when he saw them. Momo tensed, ready for a swarm of questions and people getting too close for comfort. 


Only, Katsuki was ready for that too.


“Alright, listen up fuckers because I am not repeating myself!” 


Katsuki was well known for being loud, but this was a level of focus-demanding projection she hadn’t heard from him before, and by god was it effective. Even Mic-sensei and Aizawa snapped to attention, their gazes going straight to the blonde standing between her and the rest of the class.


“Ponytail and I got our quirk swapped by one the assholes who attacked the museum. Deku, I can see you vibrating, fucking stop it. We all want to get back to school in one piece, so leave her the fuck alone. Don’t touch her, don’t ask a million questions, and for the love of god don’t startle her. She’s doing her best to keep it under control, but this shit is dangerous. Got it?” 


There was a murmur of agreement from the other students, which was good enough for Katsuki. 


“Great. We’re getting on the bus first and sitting in the back. Icy-hot, Kirishima, follow us.” 


That was her cue, Momo followed Katsuki onto the bus, giving her classmates an apologetic smile as they shuffled aside for the two of them. Still, she couldn’t help but feel relieved by the space. The benches on the bus were meant to have two students each on them, with some students taking a whole bench for themselves. Looks like that would be her today. Katsuki took the left bench at the very back, and she slid herself into the right one, careful not to touch anything with her palms, even with the gloves on. Shouto and Eijirou joined them a moment later, both looking to Katsuki for directions. 


With a roll of his eyes and a long-suffered sigh, Katsuki gestured towards the seat in front of her. 


“Kirishima, sit down and be ready to harden if you need to. Icy-hot, cool down her hands to stop her from sweating for the trip and then sit next to him. If anything happens, throw up an ice wall. Got it?”


Oh, Momo hadn’t considered that particular tactic yet, but it made sense. Even with the gloves, it’d be better if she wasn’t sweating at all. When Shouto looked to her with a silent question in his eyes, she held out her hands and gave him a reassuring nod. 


The hesitant touch of his frost had never felt better, the cold sensation ran down her palms almost making her shiver. It was relief, comfort, and safety all in one, and she exhaled shakily. 


After a moment, Shouto pulled back and silently took his seat. His movements were slow and unsure, clearly confused by this new situation. Twice he glanced towards her, and three times he glanced towards Katsuki as if he wanted to ask questions, but thought better of it. Katsuki didn’t seem to care, his red eyes stared out the window as they waited for everyone else to board. 


Izuku and Ochako took the bench in front of Katsuki, despite his grumbled protests, and the rest of the bus filled up quickly after that. Despite his excited muttering, Izuku managed to keep his questions to himself for the most part as he jotted information down in his notebook, leaving Ochako and Eijirou to fill the silence with their calming chatter. 


It was only then that a thought hit Momo, and she turned to Katsuki with widening eyes. 


“Katsuki, the explosions earlier- I could feel them, but I couldn’t hear them. And now- even when I know I’m speaking, I can’t hear my own voice. Is that- is it a part of your quirk?”


Not one word came from Izuku’s mouth, but Momo could physically feel his excitement pouring off him in waves and the questions racing in his mind as his scribbled writing reached near frantic levels. He looked like he might burst from all the energy packed into his body. 


Sighing yet again as he gave the seat in front of him a firm kick to jolt Izuku out of his manic state, Katsuki took several seconds before replying.  


“Yeah. That’s a part of it. It’s a defensive mechanism to stop the loud noises from damaging your ears. You’ll get used to it. I’ve got- I can show you some tricks for working around it. For English class ‘n stuff. Your hearing is going to be worse in general, and you won’t hear any noise you make. Also, fair warning, if you do get this shit under control enough to use your phone, touchscreens don’t like to work with it. I’ve got some special shit you’ll need to wash your clothes with too. Be careful doing homework, keep your hands clean and don’t touch the paper with ‘em. If you do get any on it then you gotta burn it and start over. Oh, and-”


Katsuki cut himself off. He’d finally noticed the silence hanging over the rest of the bus, coupled with the open staring from his classmates. Even the scratch of Izuku’s pencil on his notebook paper had stopped. Red eyes narrowed, shoulders hunching inward and sharp teeth flashed as he silently challenged anyone to speak. Everything about him screamed defensiveness, and it was only then that Momo realized what she’d just done. On his best days Katsuki hated admitting to any kind of weakness or difficulty with a passion, and here she was forcing him to put his day to day struggles on display. 


Nobody spoke, and that only made Katsuki tenser. Made his teeth grind together as he mentally filled in their stunned silence with projected judgement and shame. This was usually when Eijirou would distract him to prevent disaster, but a glance out of the corner of her eye told her the red-head was too shocked to do anything. Guess that left it up to her.


“Thank you. I really have no idea how to navigate any of this, but I’ll be as careful as I can until we switch back.”


Eyes on her, lips relaxed from their snarl, shoulders lowered just a fraction. Still tense, but better. Change the topic. 


“Ah, I suppose I should warn you about my quirk too.” Actually, now that she thought about it, Katsuki had made her the gloves earlier. While he wasn’t skinny, almost all of his frame was muscle, which wasn’t ideal for her quirk. “You used it earlier, so you should probably eat soon. I know you usually follow a strict diet, but-”


“We’re gonna need to swap diet plans, yeah. You’re gonna need to get a fuckton more nitrogen in you, and I need some actual goddamn fat on me so I don’t pass out trying to make something.”


The defensiveness was mostly gone from his posture now, replaced with a bitter resignation.


“Fuck, if this shit lasts any longer than a day or two I’m going to have to start eating sugary shit, aren’t I? Ugh. Plus I’m going to need to review chemical structures.” He paused for a moment, considering something. “It doesn’t work for anything alive though, right? I know you can do wooden shit, so it has to work for dead organic material, so what’s the limit there? Can I make viruses with it?” 


Somehow, Katsuki knowing so much about her quirk only exaggerated the strangeness of this entire ordeal. She had no idea that he’d been paying attention to her limits, let alone the finer points and gray areas. It left Momo speechless like the rest of the class, but thankfully Aizawa-sensei took that as his cue to huff a long-suffered sigh from his seat a few benches ahead of them.


“Bakugou, I feel this should go without saying, but biological warfare is illegal . Actually, new rule, no making viruses of any kind. Or bacteria. Or fungus.” 


“I wasn’t actually going to do it!” 


His indignant reply broke the tension in the bus, laughter breaking out and whispered discussions starting up again. Momo felt some of the tension seep out of her shoulders. Everything was going to be fine. The quirk would probably wear off soon anyways. 

That, as it turned out, was a lie. 


The moment they got back to school, Katsuki dragged her out to the training field. Under Aizawa’s supervision, he taught her how to trigger the explosions in such a way that it completely burned off the sweat. Her technique wasn’t perfect, but the gloves help a lot. Katsuki had apparently designed them himself specifically to help deal with all the excess nitroglycerin, and she was grateful for it. He made her two more pairs just in case, and she took to wearing them everywhere. The gloves didn’t stop the production, but they cushioned her skin from the blasts, and they absorbed the nitroglycerin so she could touch most objects without fear of leaving behind some of the deadly substance.


That same night they exchanged diet plans. Katsuki’s involved a number of meals Momo had no idea how to prepare, and while she wouldn’t usually have any issue figuring it out, almost all of them involved using some form of heat. He took one look at her still gloved hands, and promptly declared he was cooking for the both of them until their quirks swapped back. Even though Momo tried to assure him she would be fine, he took that as a challenge and refused to allow her in the kitchen. 


Oh well, there were worse things in the world. As Momo quickly discovered, Katsuki was an excellent cook. They ate with their classmates bustling by, some of them trying to cheer the two of them up, some giving them a wide berth. Izuku and Eijirou both stuck around them while they ate; with Izuku doing his best to keep his questions to a minimum, and Eijirou doing his best to stop Katsuki from murdering Izuku when he failed to do that. Momo smiled and answered what questions she could. Her hands only exploded without her permission two times, which she considered a success. She did almost break her plate the second time, but it was better than it had been before. 


Katsuki stayed quiet throughout the meal, or quiet by his standards. It wasn’t until 8 pm rolled around, his usual bedtime, that he stood and gestured for her to follow him. 


They didn’t go far, just a few paces out of the dorm where they wouldn’t be overheard. The night air was cold, a soft breeze flowing over them. For several beats they quietly stood together under the moonlight. Looking out over the scenery, Momo realized she couldn’t hear the wind rustling through the grass or bushes anymore. Even when she strained her ears listening for it. She couldn’t hear the distant city bustle, and the usually distinct chirp of crickets was faint and hard to make out. 


Turning her gaze to her companion, she wondered if Katsuki was hearing those same things for the very first time. Red eyes seemed drawn in every direction, distracted and the slightest bit overwhelmed. It must be a lot to deal with so suddenly, so she waited patiently for him to collect his thoughts. 


Eventually he did, eyes falling to stare blankly at the grass. Body tense, head down, something that looked like shame radiating out of him.


“No easy way to fucking ask this, but do you get nightmares?”


That… was an oddly personal question coming from Katsuki. Why would he- Oh. Oh. Biting her lip, she considered before answering as honestly as she could.


“Sometimes, yes. Not too often though.” After a second of thought, she added. “Do they… usually trigger your quirk? When you get them?”


“If I don’t prep for ‘em, yeah. Usually aren’t dangerous, just annoying and loud. Or at least that’s what my old hag used to say. Can’t have that in the dorms. If it starts happening to you, you’ll need to wipe your hands with that chemical shit before bed. The second and third set of gloves I made you have a pouch, stick an ice pack in ‘em to help stop the sweating. Keep your room cold as you can, and keep your hands on top of the blankets. It’s not exactly comfortable, but it works. I’ve got some other stuff you can try too if that fails.”


Questions spun in her mind, hanging off the tip of her tongue, and sending her through a rollercoaster of emotions. Momo’s room wasn’t close to Katsuki’s, but she would've heard if his explosions went off at night. They never had before. 


How many nights did he sleep like that? How many nights did he have nightmares? Why was she surprised he got nightmares after everything he'd been through? The hellish sting of the chemical he’d used to stop the explosions earlier still lingered on her palms; did he use that every night? How much pain had he been putting himself through that nobody else knew about? Was he okay? How could he be? How could he handle any of this, let alone all of it without so much as a word of compliant? 


Katsuki was still hunched inward, tension growing with each passing second. Shame and fear pouring off him in equal measure. She wanted to reach out, wanted to ask her questions, wanted to do anything to help. But she could already see how that would play out, his anger and defensiveness compounding further until he was driven away. Kindness and judgement were one and the same in his eyes, and he’d tolerate neither. 


“Thank you. I’ll try that if I start having issues.” The words left a bitter taste in her mouth, but they put Katsuki at ease. Nodding, he tilted his head up, taking in the stars perhaps, and then went back inside.


Momo needed a bit longer. With a sigh, she brought one hand up to run through her hair, the gloves making the motion more awkward than usual. The world was silent now she was alone, in a way she wasn’t used to. Silence before had always been accompanied by the sound of her own breathing, it was something she could break with a hum or a word if she felt inclined to. Now it was all encompassing, background noises having faded away from her. Silence was no longer her’s to break, having transformed into a new, heavier force.  


Cool night air wrapped around her, weighing her down just as the silence did. Just as the ache in her hands did. Just as the questions left unspoken did. 


The cold silence drove her back inside before too long. Back to the warm chatter of the dorm common room. Momo had been planning to go to bed early, but she didn’t feel like being alone anymore. Instead, she took up a spot on the couch next to Shouto who greeted her with a slight smile. Mina, ever the social butterfly, was quick to pick up on her mood and drew her into a debate on pro-hero costumes that had been waging on between her and a number of their classmates. She had to be careful not to get too into it, least her hands go off again, but it helped relieve the weight on her shoulders. 


When she went to bed that night, she lowered the temperature in her room until she was near shivering, and she had the gloves on her hands which were stuck out from the blanket into the chill. It was uncomfortable to say the least, and that was without the ice packs or chemical wipe down Katsuki suggested. She spent an hour tossing and turning before finally falling into an uneasy sleep.


Really, the explosion that jolted her awake at 6:30 am the next day shouldn’t have surprised her. 


It took several seconds for her mind to wake up fully and catch up with the world around her. Sluggishly, she realized she wasn’t cold anymore. Actually, she was quite warm. Almost unbearably so. 


Eyes snapping open in realization, Momo could only stare at the fire for several seconds until her body finally caught up and she threw the flaming blanket off onto the ground. Shit. That didn’t extinguish it. She needed something to put it out. 


Throwing open her room door, her mind focused on getting to one of the fire extinguishers, Momo almost barreled into Katsuki. If he hadn’t side-stepped her, she would’ve. 


He didn’t spare her so much as a glance. Extinguisher in hand he strode past her with a confidence that came from experience and blasted the flames before they could spread any further. Momo could only watch as he near robotically finished off the fire, collected the whole mess in his arms, and walked out with it. 


Heart racing, she took a moment to breathe, trying to calm herself down.


“What the hell-” 


Looking up, Momo saw her teacher pushing past Shouto, Sato and Tsuyu, both of whom she hadn’t noticed standing a few feet away. Aizawa, took in the scene, eyes flicking from where she was sitting on the ground to the open room door and traces of smoke still wafting in the air. Somehow, she found her voice. 


“Sorry- It’s okay now.” 


“Quirk went off?” He guessed, looking exhausted but relieved. 


When she opened her mouth to confirm, her eyes drifted back to her classmates and her words froze in her throat. 


Momo liked to think she wasn’t overly sensitive. Sure, she liked making other people happy. She liked to be liked, and she liked getting along with others. Even so, she tried not to let what other people thought get to her. She could handle people’s comments about her body, handle snide remarks about her intelligence, handle distaste, judgement, dislike, even hatred. 


But she’d never dealt with fear before. Maybe in the faces of villains, sure. Not from her classmates though. Not from her friends. 


Tsuyu, Sato and Shouto were all staring at her fearful. Their expressions were concerned, of course they were, they were her friends, but all she could see was the fear hiding in their eyes. 


Shame hit her like a speeding car. Katsuki had told her how to handle this, he’d practically handed her the answers, and she’d still messed up and scared her classmates in the process. A voice in the back of her mind screamed at her to defend herself, to tell them to mind their own business, to say it was nothing. Momo took another deep breath and shut that train of thought down. She knew better than that. These were her classmates and teacher, they cared about her. 


It’s only temporary. 


Whispered a different voice in the back of her mind, and as selfish as it was, she took comfort in it anyways. 




Right, her teacher was still waiting for an answer. 


“Sorry Aizawa-sensei, yes. I don’t know what happened, but it went off. My blanket caught fire, but Katsuki- I guess he was expecting it.”


Speak of the devil, Katsuki rounded the hallway, two blankets stacked in his arms. One was a thin canvas-like texture, while the other was thick and looked like the sort of thing used by a mountain climber. For a few steps his face was that same oddly calm expression, at least until his gaze flickered up and he froze at the sight of the others gathered in the hallway. Red eyes narrowed down and his face twisted into a snarl. 


“Alright extras, show’s fucking over. Back to your own goddamn rooms.”


Shouto opened his mouth like he was going to protest, but Katsuki cut him off. 


“Now, Icy-hot. The last thing she needs is you lot gawking and stressing her out even more.”


Reluctantly, Shouto gave one last glance to her, and when she nodded softly, all three of her classmates shuffled back towards their own dorms. Aizawa didn’t comment, choosing to give Katsuki a raised eyebrow which was ignored as he slid past their teacher into her room. 


The blankets were dumped onto her bed, revealing something that looked like a first aid kit hidden underneath them. Grabbing the kit, Katsuki strode out of her room and dropped to a crouch next to her, unzipping the case.  


“Burn the excess and take the gloves off.” 


After taking a few seconds to process his instructions and focus, Momo managed to do just that. The gloves hurt to peel off, but it was freeing. In the meantime he’d pulled on latex gloves again and didn’t hesitate to snag her hands, inspecting them carefully. To her surprise, the blisters from the day before had already healed over. There was a new, single, larger blister on each palm near the center, but the old ones were gone without a trace. 


Katsuki studied the new blisters, looking for some signs she couldn’t see before he turned back to the kit to grab a cream to spread on it.


“Red one works for the little ones, won’t numb the pain but stops ‘em from bleeding and sticking to the glove. Purple for medium stuff, numbs it a little and works kinda like a liquid band-aid. Only use the blue if you’re whole hand gets messed up. You gotta use the cleaner before you can use it, and then you have to keep your hands on ice until it wears off, but it’ll numb everything. Makes it real easy to lose control of the quirk and you can’t ignite anything on purpose if you use it. Got that?”


Glancing down, Momo noticed he was using the red capped cream. The matching blisters took up nearly half her palm, and it made her wonder what he considered medium. No time to worry about that now though, she just gave a silent nod and waited for him to finish. 


Once his task was done, Katsuki folded back up the kit and tossed it onto her desk. He stretched as he stood, an unreadable expression in his eyes. Silence weighed heavily on all three of them until he spoke. 


“Use both blankets tonight. Light one’s pretty fireproof, and both have sleeves to stick your hands out. Big one is built for arctic conditions, so you can drop the temperature down more.” Pausing, sharp teeth nibbled at his lower lip, eyes darting to their teacher. Calculating. “If it again happens tomorrow, I can wipe down your hands for you.” 


Again, she only nodded in reply. Words felt too heavy for her right now. It was enough for him, and he left with one last trailing glance between her and Aizawa. 


Aizawa dropped down next to her once he was gone, leaning up against the wall as she pulled the gloves back on. 


“You okay?”


It must’ve been minutes before Momo was able to find the energy to answer, voice feeling rough in her throat. 


“I’ve never- I’ve never been afraid of myself before. Not like this.”


“Can’t say I know how it feels.” Her teacher sounded tired, more so than usual. “But hey, if nothing else, you’ve got a damn expert keeping his eye out for you.” 


The corner of her mouth switched up, but the smile faded all too quickly as she considered that further. 


“Katsuki- Did he get his quirk from one of his parents?” 


Did he have someone to guide him through this?


“Not really. His mother can sweat glycerin, his father sweats mild concentrations of nitric acid from his hands. Neither does much on their own, but Bakugou got just about the most powerful result from the mixture.”


Momo didn’t miss how he said powerful and not lucky. Would he have said lucky a few days ago? She certainly would’ve. Now she wasn’t so sure. 


Regardless, it answered her real question. Katsuki figured all this out on his own. 


Well, if he could do it, she could too. It was… an adjustment, sure, but she was a smart, strong, capable hero in training! She could handle it until it wore off! Taking a few more deep breaths, she focused on that confidence, willing it to lend her the strength she’d need. 

A week and two days later, Momo’s confidence was all but gone. 


The first day hadn’t been so bad, sure, there’d been a number of unintended explosions, but she’d gotten through the day without blowing anyone up. She and Katsuki were both pulled out of heroics training for the afternoon, and were sent to practice working with their new quirks. Most of the session was spent on Katsuki teaching her how to trigger blasts of different strengths. She’d spent a bit of time teaching him how to visualize objects before creating them, and how to do it quickly. 


By the time they got back to the dorms, they were both sore and tired, but proud of their progress. The second night was better too, she managed to get a full night’s sleep without exploding anything this time.


Then little things started to build up. Homework was the first problem, she’d had to restart three separate assignments after she accidentally touched the paper without cleaning her hands. It was frustrating beyond belief, and left her with no time to do her usual extra studying. English class flipped from one of her favorite subjects to a hellish slog of frustration. Mic-sensei offered to let her wait on any verbal assignments until the quirk swap wore off, but dammit, Katsuki had been managing just fine in the class and so she ought to be able to too. Not only that, but he’d shared his system with her on the second day. A simple recording setup, that let her check her pronunciation after the fact. It helped, but Momo still found herself struggling to adjust. Even speaking in her native tongue was hard when she tried more complicated or rarely used words. She found herself raising her hand in class less and less as the days wore on. 


Not a day went by that she was in pain. Her hands constantly felt like they'd been put through a paper shredder, every muscle in her body groaned and protested the slightest bit of movement, and her arms felt like they might fall off from trying to handle the recoil of all the explosions. Bruises littered her skin, alongside cuts, scrapes and a few minor gashes from getting slammed around. Katsuki helped her patch up each injury without mockery, but as her body accumulated more and more damage, the only thing she could see was how little Katsuki had by comparison. He didn't have so much as a scar or flaw on his skin, while here she was during herself into a painting of red, black, and blue. Somehow, that almost hurt worse then the actual pain she was in. Still, all of that she could handle. It was hard, but she could handle it.


What really got to her was the loneliness. Her friends were trying, bless them, they really were. They went out of their way to include her. Mina and Kyouka were always nearby to fill the silence with their chatter. Izuku hung around with one of his notebooks, asking questions and offering his own suggestions for handling some of the challenges she was facing. Shouto took to icing over her hands regularly to slow down the sweating. For a few days, it was enough. Then on the third day, she hadn’t been paying attention to the sweat collecting in her gloves, and Mina had come up behind her desk.


All it took was being startled, and she’d whipped around, an explosion coming from each hand before she could think. Not little ones either. One hand completely destroyed the pencil it’d been holding, while the other launched a blast straight at Mina. 


Or, at where Mina had been a second ago.


Katsuki had been on the other side of the room, but he’d caught on to what was about to happen just in time to pull the other girl out of the way. Nobody was hurt. Even if Mina had been hit by the blast, it hadn’t been that big. She’d taken worse in training before, and Momo was sure she would’ve been fine.


The incident still shook her down to her core. 


She stopped sitting next to people on couches. Started spending more time in her room. Before she’d been very careful about touching others, but now no contact was safe. When she was around people Momo stood further back. Just in case. Just in case. 


It’s only temporary.


That was her mantra, as she stopped herself from reaching out to touch Mina’s shoulder. As she stepped back to make sure there were at least three feet between her and Shouto. As she realized it’d been a full week since she’d touched another human being. 


Touching was too risky. Closeness lead to accidents. Being near her was too dangerous right now.


It didn’t help that no matter how hard she worked during her and Katsuki’s private training sessions, she couldn’t even get basic control over the quirk, let alone any sort of mastery. Every day left her aching, sore, and feeling worse than before she started. She couldn’t handle the recoil from a small blast yet, to say nothing of Katsuki’s insanely large ones. 


Izuku suggested watching some videos of Katsuki fighting to help study his technique. As she soon discovered, he had an almost creepy amount of footage of the blond teenager in combat. He even had pre-UA videos, which she’d thought would be helpful. 


All that did was wear her self esteem down further as she watched a 10 year old Katsuki use his quirk to soar through the air, bouncing from point to point in what looked like a self-made obstacle course. He was so young, and yet he easily used blasts three to four times the size she was currently struggling with. Izuku chattered on throughout the videos too, talking all about Katsuki’s form, his strength, his mastery of such a dangerous tool. While Momo knew he was trying to help, and she knew he tended to get carried away talking about Katsuki, it still stung to hear. 

Momo wasn’t the only one who changed, and somehow that made it worse. 


To those that didn’t know him, Katsuki seemed rather unaffected by the whole quirk switch. By day three he’d figured out a modified version of his gauntlet that protected his hands, and then he was back to using explosions to fight. It wasn’t perfect, and his new blasts weren’t anywhere near as strong as his usual ones, but it was more than enough for him to get by in training. Training he couldn’t go to because he was stuck helping her try to hold her arms straight. Katsuki never complained, which was odd for him, but she still felt bad for wasting his time. Beyond the change in their schedule though, he moved on with his days as he always did.


Only, there were subtle changes in his behavior. 


He wasn’t suddenly angelic, but he got a lot more relaxed about interacting with other people. Before the swap, he’d been extremely strict in enforcing no physical contact. Eijirou had been the exception for reasons none of them had quite understood. Hell, Momo could recall overhearing others tease him for it, or for being easy to startle, or any other number of little antisocial traits of his. 


That teasing promptly died off after the switch. 


Not only because of the classwide realization of just how dangerous Katsuki’s quirk was, but also because when his quirk had been swapped to her, almost all those behaviors either vanished or been relaxed. He wasn’t suddenly touchy-feely, but he let Mina hug him with only a roll of his eyes after he’d saved her from the blast. Sudden contact still made him flinch, but the reaction was smaller and smaller as each day wore on and no explosion followed. Katsuki was interacting with other people more, pushing them away less and less, and smiling more. 


Exactly one week after the switch had occurred, Momo was down in the dorm common room. She was forcing herself to sit with Mina for a bit, she needed some social contact after all, when Kouji had come down with his rabbit, Mimi. It wasn’t uncommon for him to bring Mimi out to socialize, and it was something Momo always found herself looking forward to. 


Until today at least, when it hit her that she wouldn’t be able to play with Mimi. It was too risky, even a little bit of the sweat on her hands could kill the bunny. 


Katsuki was also down in the common room, sitting on one of the couches with his feet up in Eijirou’s lap as the two of them worked through homework together. Whatever he was talking about, his words trailed off when Mimi hopped over to investigate them. Previously, Katsuki had always avoided the rabbit, only ever nudging her with a foot or dropping her a bit of food when he thought nobody was looking. 


Today, Mimi seemed to know her attempts to befriend him would be more fruitful. Maybe she did, Kouji might’ve told her as much. 


Without any hesitation she leapt onto the couch beside him, sniffing at Eijirou first before hopping into Katsuki’s lap, little feet getting planted right on his chest as she leaned up to sniff his face. He stayed stock still the entire time, eyes wide, not even breathing until Mimi stretched herself up to headbutt his chin. 


Katsuki melted. There was no other word for it. The entire common room stopped to unabashedly stare in wonder as Katsuki’s face split into a bright, childish grin. One hand came up, a nearly invisible tremble to it, and ever so gently stroked Mimi’s long floppy ears. That earned him another happy headbutt, so he did it again and again, eventually bring up his other hand to help pet the bunny in his lap. Red eyes positively sparkled with joy, looking happier than Momo could recall seeing him before. Every touch was a new experience for him, like he was a little kid meeting a puppy for the very first time. When Mimi nuzzled under his chin, he let out an actual laugh of delight. 


After about fifteen minutes, the novelty of it hadn’t worn off, but he did get an idea. Mimi had a number of chew toys she often liked to nibble on, and after a bit of thought, he produced one from his chest. The rabbit was delighted and took to it immediately. 


Everyone in the common room, Momo excluded, had taken no less than ten photos of the two of them. Izuku appeared to be subtly filming the encounter, and Momo was pretty sure Eijirou was too. 


Five more minutes was all she could take before she made a polite excuse and went back to her room to turn in for the night. 


Jealousy and guilt twisted her stomach into knots in equal measure, because she wanted Katsuki to be happy. She really, really did. But at the same time, she wasn’t sure how much more of this she could stand. Her hands were more blisters than skin, she’d nearly fallen behind on her homework for the first time in her life, and the isolation was getting to her. The fear was getting to her. It was made all the worse every time she asked Katsuki for help, because he always knew just what to do. He always understood what she was going through, because he’d managed to deal with it just fine on his own, but she couldn’t do the same. 


Days crawled by, grinding what little self-esteem she had left into dust, until everything came to a head.


The night before had been bad; she had a series of nightmares and woke up everyone in the dorms twice before Katsuki helped her clean off her hands with the burning chemical. He hadn’t offered any judgement. He didn’t need to; her brain supplied plenty of that on it’s own. Katsuki had never woken up the entire dorm accidentally. With his explosions or without them. But Momo couldn’t even handle sleeping correctly. 


One of the homework assignments she’d spent hours on was ruined just before class when she’d grabbed it with her bare hands without thinking, sending the whole paper up in flames. Aizawa-sensei told her it was fine, she could take an extra week on it if she needed to, but all she could think about was that Katsuki had never missed an assignment before. Every part of her body ached from training, she hated her gloves with a passion because they rubbed into her blisters, clinging onto them even with the cream applied. She could feel her classmates’ worry, but any time they got close to her to offer comfort, it only stressed her out more because then she had to worry about hurting them. This particular day was extra hot too, and her sweating had massively increased as a result. During the morning alone, she’d accidentally set off four explosions. 


Lunch was supposed to be safe. All she needed to do was go outside, peel off the gloves, and enjoy her meal. It should’ve been easy. Some time alone, out where she couldn’t hurt anyone, with time to relax and think. She was downright excited for it, so much so that she wasn’t paying attention to where she was walking. 


Momo didn’t know who the boy that bumped into her was. A general education student probably. It didn’t really matter. What did matter was her gloves were soaked in explosive sweat, she was stressed out of her mind, and all it took was that light bump to set her off. 


She couldn’t hear the resulting explosion, but she could feel it rattle the hallway. 


The boy was knocked off his feet, singed slightly, but otherwise unharmed. She was knocked back too, though not quite as far.


What got to her most was his eyes. This wasn’t the carefully disguised fear lingering in her friend’s worry, or the respectful fear that kept her classmates an extra step back from her. This was a million times worse. The boy was downright terrified of her. 


Her hand reached out to help him up instinctively, and he scrambled backwards, desperate to get away from her. 


‘I’m so sorry’ and ‘I didn’t mean to, I swear’ swirled in her mind along with a million explanations and excuses, but she couldn’t make her tongue form any words. They wouldn’t mean anything to him. Wouldn’t undo what just happened.


Momo ran. 


It was the only thing she could do. She ran, and she ran, until she was out of the building. Away from people, away from the noise which was all too much, away from herself and the danger she poised to others. 


When she finally stopped, she was somewhere in Ground Beta. Thankfully, the training center was empty, so there was nobody she could hurt. Dropping down onto the ground, sobs pulled their way free from her throat, and explosion after explosion blasted out of her hands as all the frustration, pain and fear of the past week and a half overwhelmed her. 


“-Ponytail? You here?”


Of course, it had to be him. Momo tried to collect herself enough to speak, but she couldn’t find the strength to smile and say it was fine. Not right now. All she wanted was to be left alone to her misery and self-loathing. 




The shock of hearing her first name from him of all people, let alone spoken so softly and quietly, it jolted her out of her panic enough to spin around and face him.


Katsuki’s eyes were wide, there was concern in them, an unfamiliar expression for him. Concern, but no fear. Not even a little bit. He took another step closer, slow, but not cautious. 


How was it that he was the only one not scared of her? Shouldn’t he of all people know just how dangerous she was? How terribly she was at controlling this awful, awful quirk? 


Yet there was no fear in his eyes. Worry, yes. Confusion, maybe a bit. Understanding, yeah. No fear though. Despite everything. 


Shame boiled deep in her stomach, and she curled in on herself, trying to be as small as possible. He knelt down in front of her, delicate in his movements. After a few seconds, he pulled a handkerchief from his hand, offering it to her. Another reminder of how easily he adjusted to her quirk. 


Silence stretched out between them until he spoke. His voice was hesitant, comforting others had never been his strong suit after all, but still he tried.


“The guy’s fine. Recovery Girl check ‘im out and everything. He was just a bit startled, now he’s not even upset about it. It happens sometimes. People lose control of their quirks.”


“You don’t.”


Her words came out bitter, she didn’t mean it like that, didn’t mean it as an accusation. 


Momo expected him to get angry with her, or maybe confirm her failures. She wasn’t expecting him to laugh. Yet laugh he did, as if she’d just told an amazing joke. It took him several seconds to get control of himself, fixing her with an incredulous look.


“What the hell are you talking about? You’ve got my damn quirk right now, you know damn well how easy it is to lose control of.” 


“Exactly, but you don’t !” 


She took in a sharp breath, and then more words started tumbling out before she could stop them.


“I’ve known you for almost a year now, and you’ve never lost control of your quirk even once! Even when our classmates made a damn game out of startling you, you only ever used it to startle them back. You always made it look so effortless and easy, and Izuku showed me footage from when you were a kid, and you were 10 years old and you already had all this figured out without help. Here I am 16 years old, and I can’t stop myself from almost killing people after over a week!” 


Shoulders slumping in defeat, she finally dared look up at him. 


“If I can’t even handle this, maybe I’m not cut out to be a hero.” 


Katsuki, for once in his life, was stunned into silence. It took an agonizingly long minute for his brain to restart and his mouth to form words.


“Well, that’s gotta be some of the stupid bullshit I’ve heard in my fucking life, and I grew up with Deku.”


He didn’t let her get a word in, plowing on without pause. 


“You’re beating yourself up because it’s been less than two weeks and you haven’t mastered sweating fucking nitroglycerin out of your hands? Ponytail, I’ve dealt with this stuff for twelve years and I still fuck up with it.”


Opening her mouth to protest, she was cut off by one of his hands waving at her to let him finish.


“Nah, none of that. I lose control of that shit all the time, the difference is people expect it from me. I’ve been doing it long enough that I can play it off as on-purpose. It may look like I’ve got it down, but it’s nitroglycerin, it's a unstable contact explosive that'll get set off by anything. Doesn't matter how long you work with it, you're never gonna get it perfectly under control. If that’s your standard for being a hero, we might as well send everyone packing now.” 


Shaking his head, Katsuki gave her a familiar toothy, confident grin. 


“I got my quirk when I was four years old, and for the first three years of my life I was destroying everything I touched. God knows how Deku’s still alive, but if you think you fucked up today, go ask him to tell you about all the injuries I gave him by accident. And that’s not counting the mountains of ruined clothing, toys, blankets. You name it, I’ve set it on fire before. This shit isn’t easy to live with, and you’re not unworthy or whatever for not mastering it in a week and few goddamn days. Mine were weaker when I was a kid too, made it a lot easier to learn when the stakes were lower. Even then, I was still hurting myself or someone else with it more days than not.” 


Finally, Momo found her voice. 


“But- You can’t have messed up that much, you don’t even have any scars! I remember at the pool, everyone was shocked that you didn’t have any. People took bets on it. Even your hands don’t have scars on them.”


Oops, they weren’t supposed to tell Katsuki about that. He just rolled his eyes, mumbling something about 'nosy idiots with too much time on their hands' before refocusing. 


“I thought you were smarter than this Ponytail, take those damn gloves off.” 


It took her a second to realize what he’d said, but she complied out of confusion. 


There were fresh blisters on her hands from her most recent explosions. She glanced back up at him for what she was supposed to be looking for.


“You’ve been busting up your hands all week, how many scars you got from that?” 


A lot of her hand was still red and raw, so it was hard to make out any scars. Momo leaned in to inspect the healed over patches, and to her surprise, they were smooth as ever. That couldn’t be right.


“You had a scar on your left calf from when you were a kid, right? Check on that too.”


Her surprise that Katsuki remembered that tidbit was outweighed by her curiosity, so she pulled up her pant leg without a word. Only to find the scar was gone, unmarred skin left in its place. 




“Nitroglycerin isn't just for exploding things. Helps out with soft tissue repair. Can’t say I know the exact science, but it’s the same for both me and my old hag. Doesn’t matter how much damage I take, once it heals over, you’d never know it was there. Without that little side effect, I’d be more scar than not from all the times I fucked up when I was a kid. Pisses me off sometimes when people assume just ‘cause I don’t have any scars means I’ve never gotten hurt.” 


Suddenly, Momo felt silly for having been one of those people. For having made assumptions and gotten too far lost in her own head. She thought she’d learned this lesson with Shouto, but apparently not. 


Red eyes softened just a little bit, and Katsuki shuffled so he was now sitting next to her rather than in front of her. 


“Listen, I get it. This shit is hard, and you’re used to everything coming to you easily. You’re a fucking genius, you work hard, and you’ve got some common sense in you too. I mean, holy shit, you’re the number one in the heroics course at UA right now. That’s really fucking impressive. But some things take time, no matter how smart you are or how hard you work.”


He drew up his knees to his chest too, voice getting a little quieter.


“Word to the wise, don’t trust Deku’s videos to be an accurate depiction of me as a kid. Sure, I could pull off a bit of flying when I was 10, but I spent six years before that wiping out and building up the muscles. Actually, fucking scratch that, don’t trust anything nice Deku says about me when I was younger. Between his rose tinted goggles, and my need to make everyone think I was the toughest kid around, it’s pretty much all going to be an unrealistic fantasy.”


Tilting his head forward, he caught her gaze with his own, making sure she could see just how serious he was as he finished.


“It took me ages to learn how to handle any of this shit, and until we figure out how to get our quirks back where they belong, you’re just gonna have to take your time with it. But that doesn’t mean you’re not cut out to be a hero or any of that garbage. I got twelve years to get to where I was, so you don’t get to start comparing yourself to me after less than two fucking weeks. Okay?”


Tears formed at her eyes again, but this time they were tears of relief. She gave a nod, trying her best to wipe them away with the back of her hand. 


Katsuki fidgeted for a few moments, unsure of what to do with himself, before he seemed to give a mental fuck-it and awkwardly wrapped one arm around her shoulder in a make-shift hug. It was the first hug Momo had had in over a week, and the touch sent a tingle down her spine. 


“Thank y-”


She froze mid-sentence.


Katsuki’s eyes were wide too. 




He cut himself off as well, hands flying up to his ears. Momo couldn’t believe it, but she let her mind pull up the familiar shape of a Russian nesting doll, and with a mental push, the object dropped out of her arm. Both their eyes went to the doll, and then to Katsuki’s hands. Slowly, he lifted his hands away from himself, and after a few seconds a crackling pop came from his palm, bright and flashy as ever. Their eyes met. 


“Are you fucking kidding me- there’s no way.”


Momo’s mind flashed through the past week and a half. Katsuki had been around her a lot, he’d been helping her train, and helping her to keep her hands clean, but he’d always used gloves. He knew just how toxic nitroglycerin was. Meanwhile, Momo had been avoiding contact with everyone, even her closest friends. At no point could she recall the two of them touching without a barrier in between them. 


“It was that fucking easy?! We could’ve had this shit over with during the actual fight.” 


She couldn’t help herself. Momo was overwhelmed again, but this time with laughter. It had really been that easy. A week and a half of hell, and they could’ve fixed it in five minutes if they’d only known. After a few seconds, Katsuki started laughing too. There was little else they could do. 


Eventually, both of them calmed down and Momo flopped backwards onto the ground, letting herself relax for the first time since this mess began. Katsuki followed suit, letting out a heavy sigh, before lifting one hand up to release a series of sparks. She watched his face, surprised by the amount of relief and fondness in his eyes. 


“Would you have preferred they stayed swapped?”


The question took Katsuki off-guard, and he blinked owlishly at her before finding his confident smirk again. 


“Nah, no offense Ponytail, but I like my quirk more. I’ve missed flying so goddamn much over this past week. I hate eating sugary crap to build up fat stores. I like being able to blow shit to kingdom come, and everything is way too fucking loud without it. I dunno how you fuckers deal with all the extra noise all the time.” 


“But- You’ve just seemed so much happier while our quirks were swapped. I mean, there's so much you have to put up with to use yours safely. With mine you were letting people touch you, and you had so much fun with Mimi when you’ve never played with her before. It just seems unfair for you to lose that.” 


Katsuki gave another sigh, longer and deeper this time. 


“I mean, yeah, it can be a lot, but I've gotten used to a lot of the side effects. Besides, my quirk doesn’t stop me from doing all that fluffy shit, I just gotta take precautions. Once you figure out how to burn it off properly, it’s not so bad. Touch has always just been… complicated for me.”


He paused, taking in a deep breath before continuing. 


“In case you haven’t noticed, I’ve got some fucking issues. Some of ‘em come from my quirk, a lot of ‘em are due to... other shit. I’ve been working through stuff, but it’s hard. When we swapped quirks, it made it a lot easier. It was like I was a totally different person, so I was able to push my comfort zone a lot more. Getting my quirk back doesn’t mean I’m going to lose that progress though. I just have to adjust for it a bit, and that’s fine by me.”


Pausing again, Katsuki glanced down, considering something. 


“Honestly, the only person who's gonna be upset we switched back is my therapist. He was fucking thrilled about all the new stuff I was trying. But whatever, I’m still happier with my quirk, even when it makes shit harder.” 


It was Momo’s turn to be stunned. There- there was a lot to unpack there. A lot of information he was trusting her with. A potential insensitive question slipped past her lips before she could stop herself. 


“You go to therapy?”


“Yeah, have been since after the whole provisional license exam disaster. Turns out getting kidnapped fucks with your head, and that’s not even counting all the other bullshit I’ve been through.” His eyes found hers again, a meaningful look to them. “Don’t take this the wrong way, but you could probably stand to try it too. I mean, I get it, this whole situation was pretty fucked up. Still, you defaulted to blaming yourself for not being good enough awful quick. Happens to a lot of ‘gifted’ kids, and lemme tell you, it’s not a healthy path to be going down.” 


He had a point. Therapy wasn’t something she was against, if anything, she’d always thought it was an excellent tool. Just… it was an excellent tool for other people. Momo got good grades, smiled politely at everyone, and she had friends, so that had seemed good enough to exclude her from the list of people that needed therapy. Maybe she needed to reconsider that stance. 


While she thought, Katsuki pushed himself to his feet, brushing off the dust on his uniform. With a roll of his wrists, he set off a shower of sparks she’d spent the past week and a half trying to mimic. Hands now cleaned, Katsuki held out one to her, and for the very first time Momo understood how much the gesture meant. The amount of trust it required on both sides.


A smile split her face and she took it, wincing at the pressure on her blisters as she stumbled to her feet. Damn it, she’d forgotten about those. 


“Come on, let’s get you to Recovery Girl, then we can let Aizawa know this shit’s finally over.” 


Momo nodded in agreement, and the two set off together, walking side by side. There was silence between them, and something about it felt awfully familiar. Only this time a newfound confidence had settled in her. If nothing else, this last week and a half had proven one thing for sure; she didn’t have anything to fear from the explosive blonde next to her. So, when a thought struck her, she spoke without hesitation. 


“I don’t think I’ll be able to handle any explosions for the next little while, but I’d really appreciate it if you could show me how you replicated your quirk with mine. It’d be nice to have more firepower, and I’ve already spent a week and a half practicing with something similar. Might as well put that training towards something.” 


The smirk he gave her in response was downright feral, and she adored it.


“We’ll make a demolitionist out of you yet, Ponytail, mark my words. Just wait ‘till our next training session with 1-B, that girl with the stretchy hands won’t know what hit her.”


His words made her laugh again, and despite how much her body ached, despite all the loneliness and the stress, Momo still felt oddly glad that it’d taken them so long to figure out how to switch their quirks back. Really, a week or so of struggling wasn’t that high a price to pay for a new friend, particularly one like Katsuki.