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Crossing the Red Line

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Momo was in the changing room of a clothing store when she got the message.

It’s from the special app on her phone that all heroes in her agency were required to install, so she already knew it wasn’t a chat from her friends. Still, her brow raises as she taps on the notification. It wasn’t like her agency to assign work when she’s on her (long overdue, mind) day off.

𝙲𝚛𝚎𝚊𝚝𝚒, 𝚊𝚜𝚜𝚒𝚜𝚝𝚊𝚗𝚌𝚎 𝚛𝚎𝚚𝚞𝚎𝚜𝚝𝚎𝚍 𝚏𝚘𝚛 𝚙𝚛𝚘 𝚑𝚎𝚛𝚘 𝚒𝚗 𝚋𝚊𝚝𝚝𝚕𝚎. 𝙻𝚘𝚌𝚊𝚝𝚒𝚘𝚗 𝚊𝚝𝚝𝚊𝚌𝚑𝚎𝚍.

She zooms in the map below the message. The battle seems to be taking place in an alleyway just a few blocks away from where she was. They probably saw she was the closest pro hero around and thought it would be more efficient to just ask her to go instead of sending another. She’s not complaining, really; it’s always been part of the job to be on-call. Still...

Just my luck, an emergency on my only off day in months.

Momo bunches up the dresses she was intending to try on as she exits the changing room. Another message pops up:

𝚅𝚒𝚕𝚕𝚊𝚒𝚗’𝚜 𝚀𝚞𝚒𝚛𝚔 𝚒𝚜 𝚐𝚊𝚜-𝚋𝚊𝚜𝚎𝚍, 𝚙𝚘𝚝𝚎𝚗𝚝𝚒𝚊𝚕𝚕𝚢 𝚊 𝚋𝚎𝚑𝚊𝚟𝚒𝚘𝚛-𝚖𝚘𝚍𝚒𝚏𝚒𝚎𝚛 𝚝𝚢𝚙𝚎. 𝚃𝚊𝚔𝚎 𝚗𝚎𝚌𝚎𝚜𝚜𝚊𝚛𝚢 𝚙𝚛𝚎𝚌𝚊𝚞𝚝𝚒𝚘𝚗𝚜.

Her lips press into a thin line. That sounds dangerous...

“Will you be taking all of these, miss?” asks the staff with a ready smile.

“No, not today, sorry,” Momo says as she hurriedly shoves the clothes onto the bewildered staff and rushes out of the store.

- - -

Battling in a narrow alley isn’t exactly ideal for Shouto, given that his Quirk calls for wider ground. At such limited space, shooting his ice or fire would only limit his visuals of the enemy. Given that the villain is nimble and quick-footed, he can’t afford to let him out of his sight.

He’s been patrolling this part of the city for a week now in hopes of capturing this particular villain—one that has been ramping up the incidents of... random indecent behavior among citizens here. His team had looked further as to the reason behind these attacks but all they’ve managed to conclude was that the villain was only doing this for his own twisted fun. While Shouto isn’t the type to be easily scandalized, he still felt disgust upon hearing the series of lascivious acts this villain had apparently induced his victims to do in public.

Thus, he has taken to frequenting the spots where said incidents were initially reported, hoping to come across the villain and capture him. And now he’s managed to corner him into this alley.

Though with how things were working out, it seems Shouto was the one cornered.

The villain then removes his scarf, showing gills by his neck. Suddenly, they start to flutter. Shouto inevitably tenses up.

“Just a little something to loosen you up, stick-in-the-mud hero,” he says with a sneer.

They never did know how the villain activated that gas Quirk of his.

Shouto quickly backsteps then lifts a hand to cover his nose, but too late. At such a small space, it didn’t really take long for it to reach him. The sickeningly sweet scent had started to pervade his sense of smell. Figuring the least he can do is capture the villain, a trail of ice crackles from under his foot, crawling towards the still-gloating enemy. Yet, quick as always, the villain jumps onto the wall and sticks onto it like a lizard before slithering away.

The smell is starting to cloy at his throat that Shouto ends up coughing, leaning onto a wall for support. He can’t give chase now, for sure. Then he starts to feel its effects. Shouto feels his heartbeat starting to quicken. His mouth felt dry, his hands going cold and clammy. He was sure the heat he’s feeling in his body right now isn’t anything caused by his own Quirk. Even thermoregulating didn’t tamp it down.

Above all, he was also achingly aroused.

“Damn it,” he grits between his teeth as he shuts his eyes in frustration. He was too reckless, coming after the villain in such an enclosed space and basically walking into a trap. He should’ve just risked using his ice earlier than playing it safe.

His mind, muddled and hazy because of the burgeoning sensations rising in him, tries to recall the testimonials of the victims of this Quirk. Many had said the burning sensation on their body abated when they gave in to the... desires the Quirk itself was pushing them to do. Coupled with that, there had been cases of civilians who weren’t able to fulfill said desires or held themselves back who buckled under the intense body heat and died.

Shouto felt like an animal in need to rut and if he doesn’t give in to it, he may just die.

He bangs a clenched fist on the wall. “Fuck!”

“I-Is that you, Todoroki-san?!”

His ears perk up, his body shivering at the very mention of his name. Merely hearing her voice was enough to get a small groan out of him, not to mention the faint stirring of heat inside his chest. Then, eyes widening, he realizes what that was.

No. Not now. 

Not her.

- - -

As she was running towards the location, Momo indeed took precaution and created a gas mask for herself. But it seems she came too late.


With alarm, she recognizes the voice as Shouto’s. Things must’ve gone south if he sounded that frustrated. She rounds the corner and spots a figure supporting himself against a wall.

“I-Is that you, Todoroki-san?!” she calls out, not wasting any more time to head towards him.

His movements seem slow and Momo surmises he must’ve been hurt. She quickly rushes to his side, holding onto his arms as Shouto slumps against her, groaning.

“Yaoyorozu...” he manages. Even though she was holding onto the clothed sleeves of his uniform, she feels Shouto shiver against her touch. This unnatural reaction only deepens her worry.

“Were you injured?!” Craning her head around, she adds, “Where’s the enemy?”

“Not injured, enemy escaped...” He weakly pushes himself away from her, trying to create a distance to quell these heated thoughts rising in him. “Don’t... touch me.”

“W-Wait, stop moving...!” Momo only holds his arms tighter. “Something must be wrong if you’re–” She then recalls the message she received.

Gas-based Quirk, potentially a behavior-modifier type.

Momo looks at him. “Were you... hit by the enemy’s Quirk?”

He stops struggling, closes his eyes and breathes out before slowly nodding. He almost looked ashamed of it, which only makes Momo feel more concerned. He was probably trying to not inconvenience her and keep the trouble to himself...

She’s cast back to the time of their practicals back in UA, how she tried to clamp down her own thoughts and feelings, worrying that she’ll only cause him trouble. But he encouraged her to speak up and have more faith in herself... and surely she can do the same for him.


Shouto, bewildered, snaps his gaze at her.

“As heroes, we both need to support each other. There is no shame in being hurt or having to ask for help!” she says. Her eyes shine with sincerity.

Really, Shouto would’ve been touched if he wasn’t... you know... hard.

With a determined expression, she continues, “Now, tell me how I can help you out. Do you need medical attention?”

Shouto blinks.


She doesn’t know what this Quirk does.

With an awkward clearing of the throat, he begins a brief explanation.

- - -

“S-S-Sexual intercourse...?!”

Shouto runs a hand over his face in exasperation. Leave it to Momo to say that instead of simply just “sex.” She had discarded her gas mask by now after Shouto surmised that the Quirk isn’t airborne anymore, and now he can clearly see how red her face has become.

Or well, part of it. She’s kind of covering it right now with her hands.

“Yeah. But.” But I’d rather die than force it on someone, he thinks. Not wishing to worry Momo more, however, he says, “I-I’ll try... taking care of it by myself first and see if that’ll work.”

Momo lowers her hands, confused. “By yourself...? How so?”

They look at each other for three (very awkward) seconds before Momo flushes.

“I-I see...! Of course, there is also mastur–”

“So could you please leave?”

It sounded more rude than he intended it to be, but Shouto isn’t really keen on the idea of having someone watch him jerk off in some alley. Especially if said someone happens to be a person he admires.

To his surprise, she only turns her back away from him but doesn’t leave.

“I realize you’d need privacy for that but I won’t feel at ease just leaving you here by yourself when you’re incapacitated,” she says. Her voice doesn’t even show a hint of embarrassment this time. “I won’t leave you until I’m sure you’re safe, and that’s that.”

Her genuine concern causes a flutter in his chest, one completely unrelated to the Quirk. And it seems any reasoning won’t deter her from this decision as well.

“R-Right... Thank you, Yaoyorozu,” Shouto replies as he turns away from her as well. Leaning against the brick wall, he steels himself with another deep breath and surrenders himself to the fact that he has to do this now.

It’s not like he hasn’t done it before, but obviously not with someone within hearing vicinity. He unbuckles his utility belt and lets it fall; the canisters attached to them make small metal sounds as they hit the ground. Shouto then slowly pulls out his length, now fully erect despite any lack of stimulation. He hisses as wraps his warm hand around it; hell, the tip’s already moist with a small amount of cum already.

But he tries not to think of it as he starts pumping, focused at the sole need to orgasm and hopefully satisfy the Quirk enough for it to abate. The first few strokes felt like sheer bliss, his eyes fluttering shut and mouth falling open to let out a low groan. He hasn’t realized how potent the Quirk was until he’s not holding it back anymore.

Another groan as he tightens his hold onto his cock, quickening the pace of his strokes.

Hopefully he still has a face to show Momo after this.

- - -

Momo had closed her eyes, despite already facing away from him. She thought that’d be enough precaution.

Then the noises came.

Heat rises to her face as Shouto lets out another groan followed by ragged breathing as the sounds of his... ah, self-fornication assaults her hearing.

No, Momo is not imagining Shouto naked, laying down on a bed (somehow, the one that surfaces in the image is her own) with the sheets crumpled around him. Definitely not imagining him with his eyes closed and his open mouth letting our breathy gasps as he quickly pumps his hard length. And above all, Momo is most definitely not imagining herself lowering down on him, planting a kiss on his sweaty forehead as her hand takes over his own and she starts stroking his–

She covers her burning face with her hands. Since when did you become a pervert, Momo?!

But judging from the sounds he’s making, he’s probably close to finishing. Just a bit more then he’d be safe. And while she can’t promise this won’t haunt her fantasies for months after, she can at least keep all that to herself.


A loud groan, then the sound of something splattering.

Momo feels like she’s about to pass out.

She lets a minute pass by, letting him collect himself first before asking, “Did... Did it work?”

There’s a too-long silence, then an audible scoff. “...I don’t think it did.”

Momo’s stomach drops.

- - -

He’s going to die and it’s all because of some stupid sex Quirk.

Great. This couldn’t be more embarrassing. He can’t wait to watch the news flash at 7 later about how hero Shouto was found dead in some alleyway with a hard-on. Oh wait, he couldn’t even see it because he’d be dead.

The relief jerking off brought was only temporary. In fact, the Quirk is now more menacing than ever. Again and again, he tries to call forth his ice but it didn’t help at all. He thinks of his options... and finds there to be none. But then again, what was he expecting if he were to be adamant about not having sex with a stranger?

Ah, prods his subconscious, but there’s someone who isn’t a stranger who can help you right now, right?

Shouto quickly pushes the thought out of his mind.

Momo... is very attractive, and he’d be lying if he said he hasn’t fantasized about her in that way before. But above all, he genuinely does have feelings for her beyond mere lust. So if it ever happens, he wants to be proper with her... take things at her own pace and comfort.

At the very least he wanted a decent confession and a date or two first, damn it.

Still rooted in her position, Momo is wringing her fingers as she speaks up. “Perhaps we can call someone you’re seeing to come and...“

It takes Shouto a second to realize what she’s implying then he shakes his head. “I’m not seeing anyone.”

“Oh,” Momo says rather uselessly.

And even if no one mentioned a word, they both know the only option left was to do it by themselves. Right here.

Shouto fixes his pants back, never mind the tent on it. “It’s fine, Yaoyorozu. Maybe I’ll just try again... or find someone. I don’t know. Either way, you should leave.”

He can at least spare her the guilt of not being able to do anything.

With his back to her, he didn’t notice Momo turning to face him and bridging the distance between them.

Shouto continues, still thinking of convincing her to leave, “You don’t have to stay just because–“

He then freezes when he feels her weight on his back as Momo wraps him in a hug from behind.

“W-What if... I help you out...” she mumbles shyly, nervously. This close, her warm breath hits his neck.

Needless to say, Shouto’s brain short-circuits.

- - -

Of course she’s not going to let him die because of some stupid sex Quirk.

That much is certain inside Momo’s head. But she’s also been second-guessing herself about her own intentions since she found out the way to free him of this Quirk. Gauging how he might react to the idea of her offering help in that way.

It wasn’t any secret among the girls in their batch that she’s harbored a seemingly fruitless crush on Shouto all this time. And after missing her chance at confessing during their UA days, Momo felt it’s too complicated to do it now considering they’re both professionals already who have their own lives beyond going to classes or hanging out in the dorms.

Besides, she’s read his magazine interviews. The amount of times he’s shot down any questions about a romantic relationship felt almost depressing, really.

But this is a dire situation, isn’t it? Even if she does have quite a bit (oh, who was she kidding, it’s a lot) of a personal interest in experiencing this level of intimacy with him, the more pressing matter here is that she wants to help him out. As one hero to another.

In response to her offer, Shouto turns to her and clutches her shoulders. “You really... really don’t have to. Don’t force yourself, Yaoyorozu.”

“I’m not forcing myself! I really do want to help you. A-And I know I’m inexperienced but that shouldn’t matter...”

She then squeaks as Shouto tightens his hold onto her, his fingers digging into her skin.

“That’s exactly why you shouldn’t. I don’t–” Shouto pauses to grit his teeth as a wave of intense heat rolls through his body. He pants as he lets the pain subside before continuing. “Your first time... should be with someone... you like. Of all people, you... you deserve better than this.”

Just looking at how he’s pushing himself, his every word sounding pained, makes Momo tear up out of sheer frustration. How can he say these things at this time?! Person you like? Deserve better? Was this really the right time to be so... so damn righteous?!

Or perhaps...

“Todoroki-san,” Momo begins. Her hands pull close to her chest, eyes downcast. “Do you hate the idea of being with me that much...?”

Momo bites her lower lip, ashamed. It seems in the end, her attraction to him will always just be one-sided—even with a life-threatening situation looming over his head.

Suddenly, Momo feels herself maneuvered with her back pressed against the wall. The change in position was so abrupt it almost left her a bit dizzy.

Before she manages to say something, she feels Shouto’s lips on hers.

- - -

He’s truly at his limit.

Perhaps a normal person would’ve succumbed to the Quirk’s effects right away but Shouto’s body had at least been used to extreme temperatures ever since he was young. Still, one way or another, his body had to give.

And it was her question that was the final straw.

“Do you hate the idea of being with me that much...?”

Then his entire body answers.

Shouto had expected a slap on the face the moment he finally gave in to kiss her, but instead she kisses him back. They weren’t shy, clumsy kisses that he was expecting his first to be—kissing Momo’s lips felt like taking in water after crossing a desert and the more she responds to him, the more he wanted.

“I want you,” he pants as he breaks their kiss, resting his forehead against her. “You don’t know... how much I’ve always wanted you.”

The searing heat from the Quirk racks through him again and his mouth falls open with a sharp gasp, his hips bucking against her desperately. The mixture of pain and arousal was so confusing, so intense that he almost felt like crying.

“It’s... too much. It hurts,” he pleads with a sharp intake of breath, eyes shut tight.

“It’s okay, I’m here,” Momo says, planting such gentle kisses on his face. Judging from the way she swiped her thumb on his cheek, he probably did tear up already and she was wiping the traces of it.

“I want to do this with you,” she continues. “So... you don’t have to hold back.”

So he doesn’t.

His lips hungrily return to hers, his hands hurriedly bunching up her skirt to find the single piece of garment blocking him from his prize. And when his hand latches onto the lacy material, he rips it off so abruptly Momo ends up yelping.

Cupping her backside, groping and feeling the soft skin on there, Shouto lifts her up a bit and Momo takes it as a cue to wrap her arms around his neck so he can lift her easily. Once lifted, she secures her position by wrapping her legs around his waist. Momo winces as her back hits the wall.

The small part of his mind that hasn’t been completely consumed by the urgent need to get off figured he should at least prepare her so it won’t hurt for her. It is her first time, after all. Without breaking their heated kiss, Shouto’s right hand runs along her smooth thigh towards between her legs, two fingers ready to stretch her out... only to find her wet already.

Shouto breaks their kiss then, his confusion breaking through his lust-induced haze if only for a second.

Momo cranes her head to the side to avoid his gaze. “I-It’s because you kept making those noises earlier... while you were touching yourself...”

As if he needed more reason to get turned on.

He crashes their lips together again, groaning softly when Momo opens her mouth to tangle her own tongue with his persistent one. Shouto clumsily unzips himself again and pushes his hips forward, pressing himself against her entrance, letting her own slick lubricate it.

Then with the guidance of his right hand, he starts to push his cock into her.

She’s still tight, but wet enough for him to slowly enter her without much pain. Momo buries her face by his neck, whimpering at every inch that he sinks into her. Shouto presses small kisses at her temple, hoping it’ll ease her nervousness somehow. Halfway through, she lets out a pained gasp.

“Sorry... does it hurt?” Shouto asks, willing himself to pause.

Momo shakes her head but he notices the tears prickling at the corners of her closed eyes. His free hand fumbles a bit between them until he finds her clit. He slowly circles a thumb on it and Momo cries out, canting her hips forward as she clenches around him.

Shouto ducks his head to kiss her again, a slower yet no less passionate kiss as his thumb continues its touches. After a few seconds, Momo sighs blissfully against his lips and Shouto takes it as his cue to continue pushing and finally nestling his entire length inside her.

Wasting no more time, he pulls out halfway then slams inside her again. They both flinch at the first thrust but following more clumsy attempts, they soon find a rhythm to it. Momo’s fingers tangle through his hair, tugging at every particularly rough thrust.

Shouto eyes flutter as he feels himself move without much thought. This was it. What he wanted... no, what he needed. This itch, finally scratched. She felt so fucking good. Her tight warmth, her soft skin, her sweet smell, those small noises each time he slams back inside her, her lips red from all their kisses.

The fact that he’s so in love with her.

“Todo... roki...” Momo whines. He feels her clench around his cock again and realizes she might be close, which is good because he wouldn’t be able to last any longer as well.

He presses his lips against her forehead one last time before quickening his thrust, chasing for that release. A few more moments after, Momo arches her back against him and tenses.

The warmth from Momo’s orgasm was so mind-numbing that with just another thrust, he’s spilling his release inside her as well. She cries out weakly against his neck as they slow down, catching their breaths, still holding each other tight.

“Are you... okay now?” Momo says first, lifting a shaky hand to comb away his bangs from his sweaty forehead.

Indeed the hellish heat from the Quirk has already started to subside. Now he’s just left with a pleasant warmth welling in his chest.

Shouto nods and doesn’t miss the way Momo’s face softens, knowing that he was safe. She’s looking at him so affectionately that his heart can’t help but race a bit. For now though, he slowly pulls out of her, guiding her back to her feet. She stumbles at first so he doesn’t let her go just yet. They then slowly straighten out their rumpled appearances, with Momo creating some wipes to clean up their mixed release running down her thigh. Shouto had to turn his head to the side at that point.

“Yao... no, Momo?” Shouto says after some time.

Momo, who was still smoothing down her skirt, looks up.

“Can I kiss you again?” he mumbles, a blush coloring his cheeks.

Considering what they just did, this somehow strikes Momo as the funniest question he could ever ask.

“I’d allow it,” Momo says with a wry yet still fond smile.

Shouto then takes a deep breath before lifting his hands to cradle her face. He then closes the distance, lips almost nervously pressing against hers. He tilts his head slightly to capture her lips, deepening the kiss just a little bit. This wasn’t like the kisses they’ve shared in the Quirk-induced moment earlier. This was... shy, almost scared, but also warm and genuine.

Like a real first kiss.

When they both pull back, they stay still for a few seconds more, looking at each other’s eyes and finding words that were unsaid in there.

- - -

One week later.

Momo rouses from her sleep with a yawn. By force of habit, she pats at her side for her phone to check the time and her messages. Apparently, despite the soft sunlight seeping through the curtains, it’s still early; five more hours before her patrol shift begins. (Afternoon shifts are a godsend, truly.) That makes her smile. At least she has some extra time for herself.

She sits up and checks her news app, scrolling through the headlines. One particular item catches her eye:

Grape Juice Captures Lust Quirk Villain

Could that be...?

She hurriedly clicks on it and indeed, it was that same villain Shouto had a run-in with last week. The article details how the villain’s gas-based Quirk urges the victim to act out their desires.

“I don’t have my desires hidden like some fool, they’re all out in the open! So his Quirk had no effect on me!” Grape Juice said when asked about what strategy he employed to capture the villain.

A sigh. Was that really something he should feel proud of saying?

“I heard even Shouto couldn’t capture this villain. And I did! So ladies, consider fawning over me instead,” he added.

Momo rolls her eyes and puts the phone back down.

“Mhm... Are you leaving for work now?”

Looking to her side, Momo can’t help but smile as Shouto pats his hand blindly from beside her. When he finds her waist, his hold tightens onto her until he manages to pull her back into his arms.

“Not yet. Five more hours,” Momo says as she cuddles against his chest.

“Then don’t leave my arms until then,” Shouto grumbles.

“Did you know they just captured the guy?”

Shouto furrows his brow before cracking an eye open. “What guy?”

“The one you fought in the alley?” she says then immediately bursts into giggles when Shouto groans and buries his face on the pillow. “Are you still embarrassed about that?”

After a few seconds, he surfaces from the pillow but now with what seems to be a pout. It’s cute, she thinks. 

“It wasn’t exactly one of my best moments...”

Momo leans in to plant a light kiss on his nose. “I’ve said it before, haven’t I? There’s no shame in needing help.” Then a small mischievous smile. “Besides, I think you performed quite well in another aspect back there.”

If anything, the blush on his face worsens. “Does dating you mean I just get teased now all the time?” he mumbles.

A solemn nod. “Yes, I’m afraid so.”

“Fine... I guess I’ll bear with it if I get to do this.” He then pulls her closer for a kiss, something Momo’s definitely gotten addicted to lately.

“You know...” Momo says after, one finger lazily tracing on his bare chest. “If we clean up, we can go out and have a nice brunch before we have to go to work.”

Shouto smiles. “I’m not exactly stocked here with decent food, so yeah, sure.”

“Oh! And I want to swing by this clothing store quickly. You owe me some dresses. Three, in fact.” She even raises the appropriate number of fingers for emphasis.

Shouto’s smile turns into a frown. “I do?”

“Mhm, but don’t think about it too much,” Momo says with a teasing grin. She kisses his cheek before rising to her feet. “I’ll run the water. Join me if you want?”

Shouto looks at her retreating back heading towards the bathroom with confusion still etched on his face. But then he just ends up shrugging as he throws off the blanket, following after her.

He’ll figure it out later.