Work Text:
The first time it happened, you could call it something like an accident.
It’s the end of little Izuku’s seventh birthday, and he and Katsuki are standing at a crosswalk. Katsuki is beside him, crossing his arms.
They were trusted to walk home by themselves, after their time at the park. The sun had set a while ago, leaving them in soft darkness only lit by the glow of street lamps.
Izuku himself is fidgeting with his own hands, his gaze landing on every car that speeds by. He wonders, idly, about the news reports he’s seen covering children throwing themselves on train tracks—and takes a step back, recoiling at his own thoughts.
Though, when he steps back, he steps right into someones hold—Katsuki’s.
Katsuki’s hand rests, unmoving, a little bit below the base of his neck.
Izuku frowns, shifting from foot to foot and glancing just a ways back to see Katsuki also staring at each passing car. He’s not even glancing at Izuku.
“Um—um… Kacchan?”
Katsuki looks at him with cloudy eyes, for just a moment—before glancing back to the street and shoving .
A choked noise tears its way out of Izuku’s throat when his knees and palms scrape against the asphalt, head nearly slamming against the street with his own momentum.
His head bobs back up at the sound of tires screeching, scrambling up onto his knees and feeling his heart rate spike at the glow of headlights rapidly approaching.
Izuku expects it to stop, really, the sight of a frozen child who probably looks terrified but—it doesn’t. It doesn’t stop and, and—-
The pain itself is blinding—his left arm takes the brunt of the impact, twisting in a way it should not twist and the sheer force of it sending him flying.
Hazily, he thinks about the way the street drags across his skin, about the sting as the blood drips out of the open wounds. He thinks he might be screaming, but at this point, his arm hurts so badly it’s basically numb.
The sounds of the car stopping, and the drivers panic, and whatever Katsuki was saying, was muffled—for some reason, it doesn’t seem to him that the pain is what’s muffling everything.
Izuku’s blood was thrumming, a buzzy, cloudy feeling wrapping around him even as the pain started to make his entire body throb. He hears what he thinks might be Katsuki, and forces his eyes open to see a blurry figure that he thinks is probably Katsuki.
He can’t make out what he’s saying.
He kneels beside him, poking at the bent junction of his arm awkwardly, blinking down at him strangely when he shrieks in pain. Katsuki had—hadn’t Katsuki pushed him? Why would he do that? Izuku thought he would never hurt him…
But… then again… the dull ecstasy that had lit up his entire body—did Katsuki know? Is that why he did it? Then maybe… maybe…
Maybe this wasn’t so bad , Izuku thinks, drifting away into darkness.
___
He wakes up to the smell of antiseptic, and a blurry figure over him, staring down at him with worried eyes.
A low, mumbly noise is all he can manage, and the figure moves, saying something that sounds frantic.
It takes a moment, but when he fully comes to himself and blinks the remaining haze out of his eyes, he comes face-to-face with his mother. Tears have tracked down her cheeks, and her hands are clasped together, resting on her lap.
“Izuku!” she breathes out, leaning over to grasp him tightly in a hug—her hold is loose and gentle around his arm, wary of his injury. “Izuku, baby, you’re okay, ”
She cuts herself off, lip quivering violently. Shakily, she draws in a breath and wipes beneath her eyes. “You— your arm should be alright, baby, they said—six to eight weeks? But nothing–nothing permanent,”
Numbly, Izuku looks down at his own arm, casted in plaster.
Kacchan did that, he thinks absently. Kacchan did that to me. It’s all his fault.
His mother takes in a few more wobbling breaths, before clasping the hand of his uninjured arm and looking at him seriously.
“I… I know this is soon, but—what happened, baby?”
Izuku opened his mouth to reply, ready to confess exactly what had happened, but something—sweet euphoria curling around him, softening the blow and the twist and the crunch—soured in his gut when he thought about saying the words aloud, feeling sticky and wrong when his mouth tried to form them.
He didn’t say anything he had planned, tears pooling at the gross feeling. “I–I just… I don’t— I–I was… I– I had gotten all off balance an–and…” he trailed off, pulling his hand away from hers to clutch at the thin sheets.
“Oh— no, no, baby, it’s alright, you don’t— none of this is your fault, baby, okay? Don’t you ever think that any of this is your fault.”
She’s looking at him with widened eyes, brow just slightly furrowed—and so Izuku just nods. A moment of silence stretches between them before she looks away, seeming like she wants to say something before she sighs softly.
“Don’t… don’t get upset at this, baby, but the driver—” her voice catches on ‘driver’, fists tightening from where she had them balled and resting on her thighs. “---the driver said that… that he had seen Katsuki push you—”
“What?! What—that’s– Kacchan would never– ! He didn’t do anything!”
Izuku isn’t sure why he says what he did, his knee-jerk reaction to defend his best friend always , and yet… despite the sour feeling and the sticky ink of the words he couldn’t quite force out—
He found that this lie tasted quite sweet.
___
“Kacchan! Kacchan!”
Katsuki’s head practically snapped up at his call, watching Izuku wave his uninjured arm excitedly.
His mom and Inko were talking about something about the driver—suing for reckless en-dan-ger-ment, or something? He wasn’t really paying attention. His mom had brought Izuku a t-shirt and some shorts, as something fresh to change into.
Izuku bounded up to him, awkwardly taking a moment to perch himself in the chair beside him, beaming. Katsuki himself is hunched over, arms wrapped tightly around his middle.
A frown tugs on his features—he didn’t know much, but he did know that most people would consider it wrong, what he did, and that even if he himself didn’t feel the sour curdle of guilt, he could at least act like he did. Izuku… was acting weird .
He scrunched his face up, and the shining grin dropped off of Izuku’s soft features.
“Eh? Kacchan… what’s wrong?”
I pushed you , he wants to say, eyeing the cast on his left arm. I pushed you, and I thought you looked sweet when you were bloody and screaming on the ground. I think I wanted to kill you.
He doesn’t say that. He doesn’t say anything.
Izuku follows his gaze all the way back to his cast, a smaller, but still bright smile replacing his weird, dimmer expression.
“Oh—that’s… don’t worry about it!” he pauses, tilting his head slightly. “...it felt nice, for a moment. It hurt, but I felt all fuzzy and… stuff… I kinda want to do it again—not the broken arm! But… you know…” he trails off a bit awkwardly, blush creeping onto his cheeks with his admission.
For a moment, Katsuki is stunned. But then he’s fumbling, and blurting out—
“You don’t— but I… pushed you. That’s… that’s like… bad… or something,” he mumbles the last part quietly enough that he isn’t sure Izuku heard him.
He hums for a few seconds, kicking his feet.
“Hmm… I mean, yeah, I guess so , but not if we keep it between us! ‘S not like we’re hurting anyone else, so who cares if we do it again!”
That same, overjoyed look lights up Izuku’s face again with his own words, and he holds out a pinky on his uninjured hand, outstretched towards Katsuki.
“But! You’ve gotta promise not to tell anyone, okay? I don’t want you to get in trouble…”
Katsuki freezes up at the promise of more and again , but slowly smiles, too, linking their fingers and nodding, features softer than usual.
___
(Meanwhile, a blonde woman watches the exchange, nausea rolling in her gut at the obscene juxtaposition of the admission and their childish pinky-promise.
Not only had Katsuki said pushed, like that goddamn driver was right and little Izuku was a liar, but the implications of again almost made her gag—what the fuck , that’s not—that’s not fucking normal. They’re kids , they should be coloring shit and getting into petty arguments, not making pinky-promises for future brushes with death by each other's hands’.
Her best friend is a room away, speaking with her husband, and all she can think is where did we all go wrong? and wonder how they could have missed something like this.)
_____
For a moment, Izuku can almost pretend this is a normal , if rather violent and sad, situation—right up until he feels the cold kiss of metal to his neck.
He could almost pretend he really is the pathetic, trembling mess of a quirkless kid who Katsuki takes his ire out on, and this isn’t one big fucked up way for the both of them to indulge in their fantasies.
The box cutter pressed up against his pulse doesn’t do much for that thought. Nor do the red eyes staring down at him, pupils dilated and a certain kind of hunger lighting them up that Izuku hadn’t seen since the last time one of his explosions brushed a little too close to his carotid.
The very tip of the box cutter digs into the soft flesh of his throat, as Katsuki exhales a soft noise, leaning in close.
Izuku, rather belatedly, grips his wrist and tries pushing him back—succeeding in having blood drawn when he pressed back down just as hard.
“I think I want to kill you,” Katsuki breathes, “I think I want to tear your throat open and watch you bleed out,”
Perfect Kacchan, always so sure of himself, Izuku thinks, dizzy.
“K–Kacchan… come–come on… you know I’d do it for you if you— asked—!”
He hitched a breath at the slow, vertical drag of the blade, squeezing his eyes shut and throwing his head back to thump against the wall. Blood beaded along the cut—he could feel his pulse hammering right beneath the metal.
Perfect, perfect, just a bit deeper and it would kill me so easy —
“Boys? Is there an issue here?”
Cleanly, Katsuki pulls away, tucking away the box cutter in a fluid motion. He’s gotten good at that, Izuku thinks idly, breaths stuttering as he brings a hand up to press against the blood staining his neck. Not like the teacher would actually do anything.
“No issue at all, Miss,” he says—prim and yet hollow.
The teacher spares one last glance between the two, and leaves without another word.
Katsuki looks back towards him—pausing before he grabs at his wrist again and leans down, lapping at the blood pooled in his palm. A shudder ran through his entire body, leaning his weight against the wall.
“Kacchan…”
He pulls away, giving him one final look before picking his bag up off of the floor and swinging it over his shoulder.
Katsuki leaves him alone, bleeding and shaky, and yet Izuku can’t seem to shake the lasting euphoria.
_____
“Ah— ngh, ow, Kacchan, ow —!”
Katsuki popped off explosions in his palms, gripping Izuku’s forearms and baring a grin. He twisted harshly, forcing his arms back even as his protests grew in pitch. If he really hated it, he would be trying harder—and that only spurs him further.
Pinning his arms back with one hand, Katsuki leans over and messes with the sink drain, flipping the faucet and ignoring the way Izuku studied his reflection in the mirror. Viridian eyes shone with unshed tears—it was almost enough for Katsuki to call him cute.
The bathroom is pretty fucking gross—Katsuki can almost understand the way Izuku started to squirm when his weight forced him to brace his weight against the edge of the sink. He wasn’t trying hard enough— the ugly twist to his shoulder shouldn’t prove this mild of a reaction. So he’ll just make him try.
Unpinning his arms, Katsuki tangles a hand in Izuku’s hair and shoves.
Immediately, Izuku's hands fly up to push back against his hold, the wild thrashing he’s doing splashing water on the both of them. Frowning, Katsuki flips the faucet back off and tightens his hold, leaning just a bit more weight onto him, until both hands are buried in his hair and he’s towering over the smaller boy.
He watches idly as his thrashing grows in desperation, Katsuki’s own satisfaction winding around him, slow and syrupy.
Cute, he thinks, watching Izuku’s writhing slow and his chest hitch with a breath—before yanking him back and letting him hit the ground. Katsuki thought he looked rather pretty when he was choking up disgusting tap water.
Minutes later, Izuku looks up at him and gives him the sweetest smile he’s ever seen—and when he stands and immediately passes out, Katsuki is there to catch him.
_____
“---how about you take a swan dive off the roof and pray for a quirk in your next life!”
Izuku stilled, having stood there in the classroom with what probably looked like muted horror—Katsuki was probably the only person who would recognize the note of growing, palpable excitement that had sparked in him.
Take a swan dive off the roof, huh?
It would be a while longer than he could follow through with it, long after picking his notebook up from the dirty ground—he was never more thankful Katsuki hadn’t aimed for the koi pond—long after getting caught by the Sludge Villain in the alley, after seeing his dreams crushed and after saving Katsuki himself from the same villain.
When Katsuki left the scene after being checked by paramedics and giving his statement to the police, he found Izuku sitting on a curb a block over.
Izuku got up wordlessly and headed for the rooftop of a nearby, three-story building. Katsuki doesn’t try to stop him, simply taking his back and notebook and waiting on the ground.
Katsuki is the one to call the police over when Izuku hits the ground—and he doesn’t dare say a word about how he had babbled deliriously to Katsuki about how nice and fuzzy he felt when he fell, just how close he felt to flying.
Katsuki doesn’t say anything, just like usual.
Not even when Izuku’s slurred ‘ Kacchan was there to catch me, jus’ like aaallways’ makes him feel sweeter than he ever has.
_____
"Young Bakugou! Stop right this instant!"
Oh, that won't do a thing, Izuku thinks, panting almost violently. His knees wobble, buckling harshly beneath him and sending him to the ground. For a moment, he almost resented just how fucked all of his lower joints were.
As expected, Katsuki waves away the smoke that his last explosion caused, stalking forward. The grin he sports is wide, a baring of teeth.
"You've been keeping up with my quirk like the little fucking creep you are, huh Deku? Bet you know all about it by now...so how about you take a wild guess at what these gauntlets do? I'd hurry, though,"
He pauses, a few paces from Izuku's collapsed form. His smile takes on a manic edge, and when he continues speaking he sounds nearly delirious—and Izuku feels drunk on the thought that he caused that.
"Because this thing stores nitroglycerin, and I just couldn't imagine what kind of explosion it would make. Bet it would hurt. Bet it might be enough to just…" he trails off, letting the implication ring in the smoke-filled air.
Izuku wipes at his mouth, pupils dilating. "That would kill me," he breathes, feeling his pulse kick up with nothing but pure excitement.
Katsuki bares his teeth again, grin wild, holding up a hand and bringing the other to rest on the pin of the gauntlets.
"Then I guess you'd better dodge, Izuku. ”
He didn't need to be told twice.
Izuku scrambles up off the ground, Uraraka's concern and All Might's orders falling on deaf ears. Katsuki sing-songed a countdown, his pulse kicking up with every number—he was booking it down the halls, completely breathless.
Katsuki would kill me, he thinks as he nearly trips turning a corner, hearing the soft chime of his voice ring out a "zero!". Katsuki would kill me without a second thought and I can't think of anything sweeter.
He can hear his footsteps when he starts to run too, and Izuku can feel himself buzzing, thoughts running a thousand miles per hour. Katsuki is objectively faster than me, he considers, shoving off of a wall to maintain momentum when he turns.
Katsuki is objectively faster than me, and he wasn’t the one who jumped off of a roof just because his best friend told him to, so his joints are intact, too.
“Ah, ah— It’s a dead end, Deku, what’s your plan now?”
The clear note of exhilaration rings true in his voice, as Izuku stumbles forward, eyeing the window. There really was nowhere for him to go unless he jumped… in fact, it might just be easier to—
He feels the heat before he sees it, the sudden kick of adrenaline making him feel numb for a moment before he’s throwing himself to the side in something like a show of desperation.
The window he had been considering shattered, glass spraying everywhere. His back stung, his clothing most definitely singed. And yet— with the way his pulse was racing and the previous buzz was fizzing out into a fuzzy kind of euphoria, all Izuku could feel was satisfaction.
It was the same thing he felt when he was falling off of a three-story roof, too.
“Hah, you really did make it…”
He turned to see Katsuki staring at him through the smoke, red eyes alight with glee and shoulders trembling. “I thought that would kill you for sure…”
It’s so fascinating, Izuku thinks hazily, that he sounds so childlike every time this happens.
Without fail, in every near-death encounter and brush with fate, Katsuki seemed damn-near starstruck, voice wondrous and just slightly manic.
And, just like every other time before this, the blonde waits and catches Izuku as he attempts to stand, head spinning and blood pressure most definitely dropping. Just like every other time before this, Katsuki gives Izuku the most genuine smile he’s ever seen, his own excitement mellowing him out for a sweet, blissful period of time.
Izuku slips away into unconsciousness, not even noticing the way his joints ache.
___
Shouta should have known.
He should have seen the way Bakugou looked at Midoriya when he saw the crackle of a quirk brought to life, and he should have known that karma was coming to bite him in the ass.
He and Hizashi had caused so many problems for other people when they were in school—between bloodstains left in the bathroom and singed uniforms and everyone else's broken bodies and bruised skin and rescind forms, Shouta should have expected that one day he would have to deal with a pair of students just like the two of them.
All Might’s reaction was… less than Shouta expected. More focused on individual behavior than the dynamic—but, in hindsight, maybe Shouta was the only one who could see that dynamic. From an outsider's perspective, it might just look like a wild rivalry between two very powerful kids.
He paused in front of the infirmary doors, silently considering how much he valued his students' trust versus fostering a healthy, less deranged dynamic—before realizing that just maybe he could have his cake and eat it too.
Nedzu-sensei had done the same for him and Hizashi, after all.
Making sure to make his movements loud, he opened the door. He isn’t oblivious to the way Bakugou and Midoriya’s light chatter stops the moment they see him.
He clears his throat, leaning against the doorframe.
“Bakugou. Midoriya.” Shouta considers how delicately he should word this. “...All Might had some concerns about your performance in the Battle Trial today.” Ignoring how it was a stupid fucking idea in the first place.
“...All Might-sensei did?”
Midoriya’s voice is tentative—Shouta thinks he might be able to steer this in the right direction, after all.
“Yes. All Might.”
Shouta watches as his students share a look, before Bakugou scoffs and crosses his arms.
“So? ‘Fuck did he have to say?”
“He had some worries about your reckless quirk usage, Bakugou, especially concerning your support gear. And Midoriya—about your seeming lack of self-preservation and ‘poor decision’ to not engage with the villain in the scenario.”
Shouta lets them all lapse into silence, closing his eyes and resting his head on the doorframe.
He hears someone clear their throat—he thinks it’s probably Midoriya. “...and those were All Might-sensei’s critique?”
“Yes,” Shouta paused, peeling open a single eye. “I personally have a few questions concerning your behavior, if the both of you don’t mind.”
Bakugou narrows his eyes, as Midoriya stumbles through an answer, “Okay… that’s—that’s okay?”
“Is it?” he snorted, not waiting for a response. “Do you both understand why you shouldn’t have done that during the trial?”
“...yes? Yeah, yeah, I think so?” Looks to a peer for validation of feeling.
Bakugou is still squinting at him.
“Okay. And you understand why you shouldn’t have done that during a group-monitored activity, correct?”
“Yes?” “Fuck’s your point?”
Shouta raised an eyebrow at the overlapping voices. “To be blunt, I don’t particularly care what my students do in their free time,” he closed his eyes again—god he was so tired already. “It would obviously be preferable if neither of you died, and my only stipulation is that if you’re hurt, tell someone .”
He shifted his weight back onto his feet, internally wincing at the ache of his hip. He was too old for this shit.
“Other than that, you can do what you want—if it isn’t done during group-sanctioned events and classes.”
Neither Bakugou or Midoriya can seem to find an answer—and Shouta doesn’t wait for one.
“If you don’t tell me, I can’t stop you.” His hip pops, loud and slightly painful. “Take care, you two. I’ll see the both of you in class tomorrow.”
He turns heel and leaves, but not before he hears their muffled voices—
“Huh… So Hobo-sensei’s a fuckin’ weirdo—”
“Kacchan!”
___
.. sweetest shit you've ever known
sour to the bone marrow, horrid to the core
all you've got is not enough, stupid, i just want more ..