Izuku wants to know when their relationship got so strained. He wants to know when he went from Izu-nii to Deku. He wants to know when Katsuki went from that bright eyed little kid following him everywhere he went, to this distant, bratty pre-teen that did his very best to push Izuku away.
He wonders sometimes, if it was something he’d done.
He’s always doted on Katsuki, like any self-respecting older brother would. He was an adorable kid, fiery and passionate and excitable. Now, he’s rude and closed off, resistant to any and all attempts to make peace and cohabitate.
Izuku hopes beyond anything, it wasn’t his own behavior that shut his favorite person away from him.
He’d been maybe fourteen when he’d realized his own feelings, at the peak of his sexuality and interested in any and every body that wasn’t his. His adoration with Katsuki’s growing form had quickly revealed itself to be much more than innocent interest.
By five, Katsuki had already started tagging along on his runs, involving himself in Izuku’s home weight-training exercises whenever he could.
It’d been cute, at first. Izuku loved him dearly, and any extra second he could spend with his little brother was welcome. But then...
He’d started noticing.
The way Katsuki’s lithe muscles had started to develop, the way his sweat would run down the curve of his neck, pooling in hollow of his throat and just asking to be licked up. One shower jerk off session to thought of his baby brother’s lips wrapped around his cock had sentenced him to sin. He’d felt more than a little guilty after, avoiding Katsuki for the next three days out of his own confused shame.
It hadn’t taken much to tie it all together. Izuku wasn’t stupid, least of all about himself. So he’d done what any normal brother would do. He’d tucked those feelings away and threw himself into being the best older sibling he could possibly be.
Everything had been fine for years, really. He’d played the part, held his gaze back from lingering too long, and convinced himself that things were fine this way. He didn’t need reciprocity, and he’d be a fool to hope for it.
Then, sometime in between Katsuki’s eighth and ninth birthday, he’d started slapping away Izuku’s hands on his shoulders, ditching training and holing himself away in his room whenever Izuku tried to invite him to play.
It’d hurt, of course it had. His baby brother was pulling away from him, and no matter what he did, the younger just seemed to draw further and further away.
By the time Katsuki was ten and Izuku was graduating from the hero course, their relationship had all but fizzled out.
It hurt terribly, but Izuku couldn’t be sure if he’d been the one to unintentionally put distance between them in the first place. Maybe his attempts to feign normalcy had fallen short. Maybe everything was his fault after all.
Regardless, what’s done is done, and Katsuki spends most of his free time avoiding him like the plague.
Izuku spends his days adjusting to his new internship and hoping that maybe, one day, Katsuki will grow out of it.
If he doesn’t, well, Izuku will love him always.
His parents are going away for the weekend. They rarely do stuff for themselves, so Izuku had been their loudest supporter when they’d hesitantly pitched the idea of going to a hot spring resort in regards to their twentieth anniversary.
It’s both a blessing and a curse, honestly. On one hand, he gets to spend time alone with Katsuki for a whole weekend. On the other, his brother is clearly in one of his particularly bad moods, and Izuku knows that won’t bode well for any communication attempts.
“Izuku, take care of your brother okay?” His mom says, reaching up to ruffle his hair the way she’s always done. Izuku lets her, taking the gesture with pride. She’s always been his rock, despite her visible fear at his choice in careers.
“I got him. Just worry about having fun,” Izuku says, bright grin on his face at as Katsuki scoffs next to him.
Brat, Izuku thinks, despite the exasperated fondness welling in him.
“We’ll be back Monday. I put the hotel number up on the fridge, just in case.”
“We’ll be fine. Just worry about having fun. It’s two days. I’m a hero now, remember? I’m who they call if anything goes wrong.”
“Yes, well, you’re still my son. Promise you’ll call if anything?” She frets, it’s what she’s always done. Izuku nods dutifully.
“Katsuki, be nice to your brother,” she adds.
“What else would I be?” Katsuki shoots back. She opens her mouth, but Katsuki is saved from the oncoming reprimand by their father calling out from her from the car.
She shoots them one last, worried look (which Izuku soothes with his best hero-smile) before she finally grabs her purse and departs.
Katsuki floats around the house all day not talking to him, which is fine. Izuku can handle that. He’s used to it. At least they’re not actively snarking at each other. That’s always worse. Izuku never means to be rude back, but sometimes Katsuki can be so infuriating, it’s hard not to snap back at him.
Thinking about it mostly upsets him, so for their sake, and the fact that they’re alone together for the first time in years, Izuku thinks about making an attempt to reach out.
Which, unfortunately, quickly proves to be futile.
Every time he tries to approach his little brother, Katsuki gets this look on his face, half scared, half angry, and absconds from the area before Izuku can even get a proper word in. It’s frustrating, but Izuku knows that if he pushes too hard, too early, Katsuki will fuck off into his room for the remainder of the evening, and Izuku has no chance after that.
So he lets his brother duck him, observes his increasingly frustrated glances, and pretends like he doesn’t notice.
Maybe it’s a good sign. Katsuki’s looking at him, at least. That’s better than being outright ignored.
He figures he’ll let Katsuki have the downstairs space to himself for now. Izuku had been up early for a run, and he could do with a little extra shut-eye before he starts getting irritable.
Izuku awakens from his late afternoon nap to the smell of something cooking. It smells good, and there’s only one other person in the house right now, which means...
Katsuki’s making dinner.
He’s only eleven, but he’d always been far more interested in spending time in the kitchen with their mom than Izuku had ever been. Whatever he’s cooking, it smells amazing, and Izuku’s stomach growls as he drifts downstairs.
He pauses at the entrance, leaning against the frame and taking a moment to stare at the pretty little image of Katsuki’s back, waist accentuated by the apron he’s got tied around it. Izuku looks him over, from the broadening sweep of his shoulders to the plush curve of his ass. He’s wearing little more than boxers and a black tank-top, the pale length of his legs on full display.
He’s truly growing into himself, muscles gaining proper definition from how hard he’s been training on his own. He’s a proper hero-hopeful, already on track to attend Yuuei. Izuku is so proud of him some days it’s overwhelming. He wants, so desperately, to be able to celebrate his brother’s successes with him, but they’re past that now.
He spends another long moment admiring Katsuki before finally shaking out of his reverie and drifting closer to the stove.
He waits until he’s right up behind Katsuki before caving and resting the tips of his fingers against his lower back.
“Fuck!” Katsuki jumps about a foot in the air, splattering what Izuku now recognizes as curry against the length of his apron and rounding to snarl up at him. “Don’t do that!”
Izuku holds his hands up in a placating gesture, forcing down a laugh and replacing it with an apologetic smile. “Sorry, sorry.”
“It’s almost ready, so back off.” Katsuki growls, glancing down at the mess on his apron as his frown deepens.
“I was lured in. You made my favorite,” Izuku says, all smiles. It’s a true delight to watch a soft blush appear on Katsuki’s face, highlighting the bright red of his eyes as he turns his head away. Izuku wonders about that. Wonders what that means.
Katsuki’s never been a particularly blushy kid. His body leant more towards tears than redness, crying when he was frustrated and hating it. Heroes didn’t cry, he’d always said, and Izuku had always gently reminded him that everybody cried, even heroes.
He looks up again, meeting Izuku’s gaze with a frustrated look of his own.
His brother’s flush only deepens the longer Izuku stares at him, and Izuku doesn’t quite know how to parse through that one. It’s been ages since they’ve even been this close. He doesn’t have a frame of reference for Katsuki anymore. Has to go off what he remembers, and what he’s learned from others thus far.
“I know it is, Deku.” And there it is, that name that Katsuki had so lovingly started calling him when their relationship had fallen apart. Izuku will admit it is a little clever.
Doesn’t much stop it from hurting, though.
“How bout I set the table. We can eat together, yeah?” Izuku suggests, moving in a little closer on a whim and watching as Katsuki bites his lip and breaks eye contact, glaring at some spot on Izuku’s chest.
“Fine, whatever. I don’t care.”
It sounds like he very much does care, but Izuku will count it as a small win. And he’ll tuck his brother’s reaction into a little observatory in his head.
This is new. This is different.
They eat dinner in relative silence, and Izuku stares at him the whole time. Katsuki very deliberately doesn’t look at him now, a faint flush on his cheeks throughout the whole meal.
It’s endearing, in an annoying kind of way. He wishes Katsuki would catch his eye, so he could read him a little better, but the kid stares down at his plate aggressively the whole time.
Izuku tries to make stilted conversation about Katsuki’s school life, which goes about as well as you’d think.
“How are classes?” Izuku asks.
“Fine.” Katsuki has never sounded so clipped. He tries again.
“Any subjects you like?”
“Any – any boys?”
Katsuki’s head snaps up at this, the same fearful expression from earlier on his face as the color on his face darkens to a deep maroon. He stares at Izuku for a beat longer than he should, gaping at him before his brows furrow and he goes back to glaring at his food.
“N – No. No boys.” Katsuki answers finally. Izuku tries not to focus on the stress placed on that word. Doesn’t truly understand what it could mean. He’d seamlessly answered negatively to liking girls, so why stress the “boys”?
Izuku has a difficult time not letting his thoughts get away from him.
He tries not to set his expectations too high. This is Katsuki, after all. Even when they’d been good, he’d always been a bit difficult, always pushing buttons in all the wrong ways.
Not much he can do about it, expect find a way to navigate around him. Izuku loves him in spite of it all, or maybe, because of it all.
They finish eating, and Izuku’s mind is a whirlwind of desperate hope. Maybe he’s been reading everything wrong. Maybe Katsuki’s been avoiding him because he has something to hide.
He realizes, distantly, that this might be his only shot. He just wants Katsuki to want him. He’s so tired of holding back. He just wants to be able to spend time with his brother, without worry about why Katsuki hates him now, and why he can’t break through to him.
“I can clean up,” Izuku offers, standing and collecting his plate. Katsuki had cooked, after all, it’d only be fair.
“I got it.” Katsuki snatches it out of his hand, moving smoothly to the sink and turning on the water. “You can go do whatever.”
Izuku’s eyes widen, but he sees the tight line of tension in Katsuki’s shoulders, the way he has them bunched up to his ears – and he’s not done pushing.
This is it. This might be his chance. This’ll tell him if he’s projecting or not. Izuku just needs a little bit of confirmation. He’s still stuck on the boys. If there were no classmates he liked, and no teachers, perhaps... an adult?
Does he dare..?
“C’mon,” Izuku murmurs, moving up behind him, caging his little brother in against the counter. He raises his hands, sliding them down the length of Katsuki’s bare arms and tangling their fingers together under the spray. “Four hands are faster than two.”
Katsuki freezes up completely, and Izuku can feel the heat pouring off him in waves, can hear the soft sound of his baby brother’s breath hitching. Despite this, he doesn’t get shoved back, and seconds stretch on in silence before Katsuki finally takes a deep breath and nudges at Izuku’s hands with his own.
“It – it doesn’t work like that.” Katsuki says quietly, like he’s not sure how to disarm the situation. Like maybe, just maybe, he’s not sure if he wants to.
“Sure it does. You don’t trust your big brother?” Izuku says playfully, nose buried in Katsuki’s hair. It smells faintly of the shampoo they both use, and the familiarity is a comfort.
“W – why are you doing this?” Katsuki asks, and Izuku picks up on the faint tremor coursing through him. He’s affected by their proximity, and Izuku couldn’t have hoped for anything better.
“Because I miss you. I want to spend time with you. Is that too much to ask?” Izuku admits, because it’s nothing if not the honest to god truth. Katsuki goes silent for long enough that Izuku is doubtful he’s going to respond. If it wasn’t for the way Katsuki is absently brushing his pinky against Izuku’s own, he’d think the kid had forgotten he’s here.
Finally, after what feels like an eternity, he feels Katsuki sigh against him. “Just – fine, just stop, okay? I’ll hang out with you later just please move.”
Izuku’s smile is the biggest it’s been in weeks, and he can’t help but press a quick kiss into his brother’s hair as he squeezes his hands.
“Great! I’ll pick something to watch while you finish up, then.” Izuku says easily, detaching himself from Katsuki’s back and putting some distance between them. Katsuki’s rigid posture doesn’t loosen, but that’s fine, Izuku will work on that later.
Katsuki’s aware of him. God, Izuku can’t stop the giddy excitement he feels crawling up his throat. He wants to laugh, wants to cry.
It’s still unconfirmed, of course, but this, whatever this is, is definitely something he can work with.
He heads back to the living room, throwing on a random movie they should have both seen at this point.
Katsuki finishes up quickly, and Izuku hears him bang around in the kitchen for longer than he needs to before finally appearing next to the couch.
Katsuki fidgets like he’s not sure what to do, fists clenching and unclenching as he glares at the sofa like it’s personally offended him. He seems to come to some sort of decision though, heaving one massive sigh before planting himself on the very far end, as much space between them as the couch will allow.
Izuku’s not having that, and lightning quick, he’s reaching over, grabbing Katsuki’s forearm before the other boy can dart away
“God, you’re difficult.” Izuku says, affection saturating his tone as he yanks Katsuki towards him. He may or may not use just a little bit of his quirk, making sure his little brother crashes into his lap in an undignified heap.
“You promised you’d hang out with me,” Izuku says, smiling down at the fussy little thing in his arms.
“That doesn’t mean sitting in your lap!” Katsuki yells, entire face going red. Izuku shrugs, pushing him around so they’re flush against each other. It’s telling that Katsuki doesn’t immediately try to struggle out of his grip.
“Yeah it does. You didn’t set up any hang out boundaries. And this is how I want to hang out. You uncomfortable, or something?”
“I’m not.” Honestly, Katsuki’s stubbornness is going to get him into all sorts of trouble one day. Right now, it only works in Izuku’s favor.
“Alright, great.” Izuku says, hitting play like that settles the issue. Katsuki’s body is still coiled up, like he’s ready to run at any moment.
But he doesn’t.
He doesn’t move an inch – not when Izuku settles his chin on his shoulder, and not when he sneaks both arms around him to hold him closer.
Izuku can almost hear his heart thumping, can surely feel it, anyhow. Katsuki is nervous, and isn’t that something? Izuku never would have guessed.
A part of him wants to take this slow, wants to poke and prod at this new revelation, but he’s always been a little impatient. And besides, who knows when they’ll have the house to themselves again?
He lets his hands drift, rubbing a slow circle against Katsuki’s stomach before letting his fingers skim along the edges of his shirt.
“What the fuck are you doing?” Katsuki says, voice high and alarmed.
“What? I’m not allowed to hug my baby brother anymore?” Izuku answers, the picture of nonchalance.
Katsuki squirms, the way he always does these days when Izuku calls him “baby brother,” when he ropes him in to some sort of stilted conversation.
“This is more than a hug,” he says, almost petulant.
“I just wanted to say thank you. For dinner,” Izuku says smoothly tucking his face into the crook of Katsuki’s neck and inhaling deeply. He smells like the spices he’d cooked with tonight. It’s comforting and divine and Izuku wants to sink his teeth into him.
“M’not gonna let you starve just cuz mom’s gone for the weekend... You’re a Pro Hero,” he mumbles, and God, he’s adorable. Izuku is overcome with how much affection he holds for him sometimes.
“I’m still an intern,” Izuku corrects, laying the flat of his palm overtop Katsuki’s shirt.
“All the more reason.” Katsuki wiggles uncomfortably, but he’s not pulling away, not entirely.
“You’re so considerate.”
“No really, you are. It’s something I love about you,” Izuku murmurs, brushing against the soft skin of his navel and toying with the edge of his boxers.
“Deku, what –”
“I’ve seen you looking at me, you know.” Izuku cuts in, fingers stroking lazily at the soft skin, still hairless and so, so smooth.
“W – what?”
“I didn’t realize, at first. Thought you were just being a brat. Never would’ve guessed you had a crush.” Izuku says, finally giving voice to his suspicions. It feels like he’s airing out both of their dirty laundry in one fell swoop. But nothing ventured, nothing gained, right?
He’s waiting for Katsuki to deny it, for him to shove him off and try and run, to hurl accusations at him and call him crazy.
Instead, his little brother goes deathly silent, body falling into an almost unnatural stillness as Izuku continues to run his fingers against him.
“Am I wrong?” He continues, fingers dipping lower, teasing just milimeters away from the base of Katsuki’s cock. He feels the muscles there jerk in response, and God, he wants so badly to sink his hand down just a little bit lower. “Katsuki, answer me.”
“How’d you know?” He asks in a rush, breathless and scared, like he’s not even sure he should be admitting to it. Something tense unfurls in Izuku’s chest, blossoming into a happiness so great he feels almost dizzy with it.
“I didn’t. Not until today, anyway.” Izuku says, rewarding honesty with honesty. He wants to lie and play the all-knowing big brother, but he knows that’s not what Katsuki needs from him right now. “I thought I always told you that you could come to me with anything.”
“This is different.”
“I get that, but I hope you know how wrong you were,” Izuku says, punctuating his words with another gentle brush of his fingers, pressing down. Katsuki inhales sharply, body picking its little shakes back up as his toes curl.
“Doesn’t – doesn’t change anything. Doesn’t mean you – you, fuck, Deku stop touching me.” He whines.
“No.” Izuku loops his other hand around Katsuki’s wrist, pulling his hand away where it’d started to drift towards his own. “You’re right, though. It doesn’t change anything at all.”
“See? Now get off –”
“You’re stubborn to a fault, you know that? Can’t see what’s right in front of you once you get an idea set in your head.”
“Stop talking in fucking riddles.”
“Yikes, where’d you pick that up from?”
Izuku sighs, but he’s smiling. He can’t not smile. Not when he’s got his little brother in his lap, tenting his underwear and admitting that he’s got a crush on him. Not even in Izuku’s wildest fantasies had he ever dared picture this.
“I love you.” He says, simple and easy, like he says the words every day. “I’ve always loved you.”
This doesn’t seem to make Katsuki happy, and he makes a frustrated noise and tests the grip Izuku has on his wrist. He’s got a pretty good idea what Katsuki’s thinking right now, and when Katsuki says, “Brother’s don’t –” Izuku is quick to silence him.
“Brothers don’t spend their time teasing their little brothers until they’re hard,” he says, letting his hand drift to the side and scratch lightly at the juncture between Katsuki’s thigh and his crotch. It earns him a small moan and a violent shiver. It’s perfect. Katsuki’s perfect. “But here we are.”
“I don’t –” Katsuki starts, frowning at nothing in particular now. “I don’t understand what you’re trying to say.”
“I’m saying that I want you, all of you. Especially this. I’ve always told you that I love you,” he explains, pressing a kiss into the side of his neck. Katsuki leans into his lips, and Izuku feels his heart soar. “You starting to see how much, now?”
“I – I’ve never done this before,” Katsuki admits, and Izuku would fucking hope not. He’d gut anybody that’d think to try. This is his baby brother, his pride and joy, and Izuku is never going to let anybody else touch him.
“So let me.” He doesn’t get a no, which Izuku chooses to interpret as an enthusiastic yes. It’s the most he’ll be able to squeeze out of the kid. He withdraws his hand, itching to touch, but figuring he’d exercise a bit of restraint, instead choosing to rest his palm overtop his boxers, cupping his erection.
“You started playing with yourself yet?” Izuku’s voice is low and heavy, laced with intent. Katsuki warms in his grip. He awarded with a shake of his little brother’s head. “Really? Not even a little? How about in the shower. I know you’ve started getting hard.” It’s an assumption, but Izuku had starting having wet dreams around ten. He figures, especially if Katsuki’s been dealing with a crush, he’d probably have started around the same time.
“It’s embarrassing!” Katsuki blurts, and Izuku stretches his neck out to try and get a better look at him. He can see tears prickling the corner of Katsuki’s eyes, but he’s not worried. His little brother has always been a frustrated crier, much to his mortification.
“No it’s not,” he starts. “There’s nothing embarrassing about making yourself feel good.” Izuku’s words are carefully measured. Just the right amount of casual to calm the little spitfire in his arms. He presses his hand down a little more firmly, rubbing at the small bulge and trying to keep his own arousal at bay.
Katsuki doesn’t respond, just whines softly and trembles harder. So Izuku pushes past that one, last little barrier and says, “I could teach you, if you want...”
Katsuki lets out another noise at that, louder and a little desperate. Izuku grows bold, flexing his fingers and fondling him through his boxers.
“It’ll feel real good, I promise,” he continues, right against Katsuki’s ear. He’s awarded with another full-body shudder, and he doesn’t wait for the go ahead before sliding his hand into the opening of Katsuki’s underwear and palming him roughly – skin to skin.
“Ah – haah!” His little voice is like music to Izuku’s ears, and he can’t stop the way his dick begins to fill, the sensation of finally getting his hands on the one thing he’s always wanted overriding his impeccable self-control.
Well, maybe not to impeccable anymore.
“See? Doesn’t that feel good?” He asks, kissing the shell of Katsuki’s ear and coaxing his cock out of the gap in the fabric. He turns greedy eyes downward, taking in the sight of his little brother’s most private spot, still fully covered at the very tip with foreskin.
Izuku slides his fingers underneath the soft skin immediately, prodding at the slit as Katsuki’s hips jerk back and he whines. “Deku!”
“Shh, shhh, m’gonna roll this down, okay? It’s gonna feel weird, but I’ve got you,” Izuku murmurs, gently working the delicate skin back from the tip. If Katsuki hasn’t touched himself – and God, isn’t that a thought – then chances are he’s never pulled his foreskin back enough to really reveal the head.
Izuku’s mouth waters at the very thought of teaching him how to do this. There’s a sick sense of delight knowing he’s the first, even before Katsuki himself, and his cock pulses against the small of Katsuki’s back.
“D – Deku it hurts – nnh.” Katsuki says, voice cracking on the miserable nickname.
“You’re tough. I know it feels a little strange, but it’ll be over in juuust a second,” Izuku tries to keep his voice as soothing as possible. It can’t be that bad, not with the minimal resistance the soft skin is giving him. He’d have stopped if there’d been less give, but Katsuki is still hard and leaking. It’s a mouth-watering sight, and his own hips jerk in satisfaction when the skin slides easily over the widest point and nestles prettily just under the head.
“There we go...” He mumbles, giving Katsuki a few congratulatory strokes as his brother pants in his lap. “See? Now you’re all grown up.”
Katsuki’s dick paints a pretty picture, fleshed cherry red at the tip and oozing a pearl of precum that Izuku smears back into the slit with his thumb. Katsuki’s a mess of movement, every little shiver and twitch only feeding Izuku’s hunger.
He grips him loose, and Katsuki is still smaller than he will be when he’s older, so Izuku’s fingers touch on the wraparound. Katsuki’s knees start to come together as Izuku starts stroking him, rolling his hips up, but body trying to hide itself.
“Nu-uh, nope, none of that” Izuku hooks his feet around Katsuki’s ankles, pulling his slim legs apart and keeping them in place. Katsuki lets out a garbled little noise at the handling, burying his face into his shoulder to hide at least some part of himself.
“See how much your body likes it? You’re responding so well for me. You’re doing so good, Katsuki.” He’s babbling praise, and it’s worth it for the desperate whine he gets in return.
He twists his hand just so, swiping over the slit with every stroke as Katsuki breathes, “Deku.”
“C’mon. Call me what you used to call me,” he urges.
“I - Izuku...” Katsuki whispers, Izuku’s hand a tight circle for him to fuck into. His hips jerk up of their own volition, and Izuku practically crows in delight. He’s achingly hard himself, but that’s secondary to doing the one thing he’s wanted for years.
“Not quite,” he says, squeezing at the sensitive length of him. “Come on, you know what I want.”
He strokes him slow, a firm, lazy pull that has Katsuki trembling in his grasp. Izuku slides his other hand up, smoothing over his brother’s barely there abs and up to his chest, seeking out a small, rosy nipple to roll between his fingers.
“Izu-nii!” Katsuki wails, back arching as his chest follows the tug of Izuku’s fingers. He yanks hard on the little bud, twisting just on the side of too-tight and Katsuki lets out a high pitched cry.
“Yeah, just like that.” Izuku breathes, pressing a kiss into the side of his baby brother’s jaw before opening his mouth so suck a soft little mark into the underside. He picks up the pace, jerking Katsuki in short, efficient pulls and muffling his own groan into the soft juncture of Katsuki’s neck.
“Say it again.”
“Izu-nii! Izu-nii please nnh –”
“Fuuuuck.” The swear is out of him before he can catch it, but it doesn’t matter. The kid’s movements start getting more erratic, and Izuku slips his hand back down to rest firm against his brother’s tummy, holding him in place.
He feels little pinpricks on his knees own knees where Katsuki digs his nails, and it stings in just the right way. He pulls the small body against him firmly, feeling Katsuki’s abdominal muscles contract in that way that tells him his baby brother is close.
“You can let go,” Izuku coaxes, scratching his nails lightly against Katsuki’s stomach, catching on the soft dip of his bellybutton.
“F – feels like I – I’m gonna pee,” Katsuki moans, voice sluttier than Izuku’s wildest dreams.
“You’re going to come.” He explains, like the good older brother he is. “You’re going to come for me, and you’re going to moan loud for your big brother, okay?”
Katsuki obliges him, obedient for once in his life, mouth dropping open and letting out a loud wail of, “I–Izu-niiiiiii !” as his dick jerks in Izuku’s hand. Katsuki’s entire body goes rigid, cum arching up into the air and splattering weakly against the edge of the coffee table. Izuku makes a mental note to clean that, later.
For now, he’s got his hands full with his trembling baby brother, stroking him through the aftermath until he’s making feeble little attempts to get away.
Izuku shushes him, plants an array of butterfly kisses against the line of his neck and finally takes his hand off Katsuki’s cock, moving up to resume rubbing at his navel.
“You did such a good job.” Izuku murmurs, lazily tracing patterns around Katsuki’s belly button as his body gives off one last shudder as he finally relaxes and melts back into him, head lolling back against Izuku’s shoulder.
“Sh – shut up.” There’s no real heat behind it, and Izuku grins down at him before swooping in quick to plant a light kiss against Katsuki’s pout.
“Mmh. Sorry, kinda hard when my little brother’s this adorable.” Katsuki’s face goes from pink to red, and he turns away from him with a huff.
“You really are embarrassing, you know that?”
“Yeah,” Izuku says, gaze softening as he looks at that wild head of spikey hair, overcome with just how much he adores this kid. “But you love me anyway.”