Chapter Text
Being in different streams meant that Katsuki didn’t have to put up with that incipit idiot from 1B unless their classes were training together. He heard him, of course, because his voice carried like nobody’s business, and his goddamn tone just got under Katsuki’s skin, but he didn’t have to see him all that often.
Which was good for the school more than for Katsuki really. Because every time they did see each other, something usually blew up.
Or some one.
“Temper, temper,” Neito had this way of saying words, just saying them with his open goddamn mouth, that drove Katsuki up the wall. It annoyed him. Everything about the brat annoyed him. It wafted off him like a bad smell, that insufferable, proud, petty, stupid–
“You shut your mouth when you’re talking to me!” Katsuki spat back, and Neito’s eyes widened a little.
“Now that would be a feat,” he grinned, “I’d have to borrow someone for that.”
“I’ll borrow you, you fuckin’--”
It hadn’t ended well, that first meeting. It had ended in shouts and the two classes not so much squaring off as holding each of their class idiots at bay. Eventually Neito got carried off by Kendo, and Katsuki walked away on his own, absolutely not sulking and playing the argument in his mind over and over.
Because honestly when it came to fisticuffs, he could destroy that kid, blow him right the hell up before he got anywhere near Katsuki to touch him. But with words, well…
And it wasn’t as though Katsuki was stupid, he was far from it, but when his pride was rubbed against his mind reacted. He went from vaguely rational and has-good-potential to neanderthal. And he hated it. Because unlike Eijirou, who was just as much an Alpha as Katsuki was, or even that asshole Neito, Katsuki’s mind short circuited when his instincts were involved.
“An Enigma, how curious,” the doctor had said, and Katsuki had given him the most withering stare he’d been capable of as a thirteen-year-old.
“No, I’m the mystery wrapped in it,” he’d bitten back, and the doctor took a moment before a chuckle rose in his throat and he’d shaken his head.
“No, Bakugou, I’m saying your presentation. An Enigma. It’s quite rare, you must have the gene for it in your blood line.”
“I don’t give a shit,” Katsuki had snapped, fidgeting with his hands as one knee bounced up and down nervously. He’d thanked his lucky stars this appointment hadn’t needed his parents’ presence, he’d be melting the goddamn floor to sink through it now if it had. “What does it mean?”
“Well, for all intents and purposes, you’re an Alpha. When it comes to finding a mate, if you wish to start a family and pass your genes along, you’ll need to bond with an Omega for healthy pups. But of course, Beta and Alpha pairs are becoming less rare, there’s nothing stopping you should the chips fall that way.”
“For all intents and purposes,” Katsuki had chewed his lip. “What aren’t you telling me?”
In truth, Katsuki’s Enigma status meant little outside of medical statistics where he was considered a valuable and fascinating anomaly. He was just as virile as other Alphas, had similar instincts to seek, protect, and provide for their mate. But biologically he didn’t get rut cycles, he didn’t need to take scent blockers to keep his classmates from losing their minds around him. He could function when he needed to, and fuck when he wanted to.
Honestly, a pretty decent roll of the dice.
But the problem was, that it wasn’t. It wasn’t because kids were assholes, and anyone slightly different was public enemy number one. An Alpha without a rut period? Broken, damaged, sissy, useless. They’d never learned about Enigmas in health class, it was so rare that it wasn’t even in the curriculum. And Katsuki didn’t have the energy nor the fucks to give when it came to explaining himself to anyone.
Fuck them, goddamn extras weren’t worth his time.
But it did make school life that little bit more lonely.
That, and Katsuki’s strength was unparalleled, to the point that when his results had come in, Aizawa had taken him aside for what Katsuki thought would be the most humiliating private chat of his life. It had actually ended up being a somewhat gentle– for Aizawa– warning against letting his emotions get the better of him. Because unlike the other Alphas in his grade, hell, even in his school, Katsuki was capable of incredible things. Powerful things. Dangerous things.
And it was his responsibility to keep them in check, its own particular kind of training regimen on top of his hero work and classes.
So he did. He kept his emotions in check… usually. He tried, okay? Fuck. But sometimes… sometimes.
The next time Neito tried to get under his skin, Katsuki ignored him. He gritted his teeth and swallowed his pride and solved simultaneous equations in his head to not. react. to. him. And it had worked… kind of. Because other people were around and he didn’t want to get goddamn detention for putting that stupid kid in his place.
But then he’d overheard some morons muttering about how Neito was the only guy who could get away with ribbing Katsuki without consequence and that had been it.
He shoulder-checked the guy in the hallway between classes and shoved him against a wall before blasting a hole through it right next to his head.
“Don’t fuckin’ test me, you goddamn mockingbird.”
Neito’s eyes had grown wide, red-rimmed irises flashed for just a moment as his inner Alpha growled, and that smile had been just as stupidly placid as before. As though nothing could move him, nothing could faze him.
“Noted,” he murmured, before Katsuki felt something sharp and stinging hot against his midriff and one of his own blasts ripped through his uniform and shoved him across the room so hard he left nail marks in the floor where he’d tried to slow himself down.
“Keep to your trajectory, then, cruise missile,” Neito drawled lazily from somewhere above him, “you’re preprogrammed aren’t you? Can’t think for yourself.”
“I will fuck you up–!”
“Just try it, Bakugou!”
“I’ll–”
“Nope!!” the voice made the whole damn room shake, the whole damn building, and Neito stumbled and landed in a half crouch next to Katsuki. From down the hall, Mic glared at the two of them, arms crossed and head tilted to the side. “Take the Alpha posturing to the training gym.”
Katsuki blinked. “But–”
“You’ll get into it at some point,” their teacher shrugged, stepping closer and bending damn near in half at the waist to look at the two of them. “You always do, you Alphas. Better use the energy on something practical that’ll help you in the long run. Even if it will mean detention later.”
Neito swallowed before that damn mouth of his–
“But sir, aren’t you an Alpha?”
“Yep!” Mic straightened up again, arms still crossed, grin now a little more feral across his otherwise jovial features. “So I’d know better than most. Get it over with, crawl away to lick your wounded pride, and remember that your essays are due on Friday by eleven, for both streams.”
“What?” Katsuki just blinked at him. What the hell was going on?
“I’m not giving either of you an extension just because your hormones are raging.” Mic shrugged, before turning on his heel to leave. “Training gym, or shake on it like gentlemen, your decision, but don’t do it here!”
The silence rang louder than Mic’s initial intervention had, and it took Katsuki a few moments to realize his hands were shaking, adrenaline cool beneath his skin, heart beating too damn loud.
At least most of the students had cleared the hallway now, not willing to be late for class just to watch a showdown, and part of Katsuki knew that he should get up and leave, he should be the bigger man here, but he just couldn’t stand it anymore.
Glancing over at Neito, he saw the other Alpha in a similar position. At least they agreed on something. That riled Katsuki up even more; he didn’t want anything in common with this… this…
How they made it to the gym was a mystery for both of them, but when they stepped into it, Katsuki kicked the door shut and tossed his bag and ruined blazer to the floor under one of the benches.
“No hero costumes,” he said, voice ringing through the hollow empty place, “no gadgets, just us. One on one. Let’s fuckin’ settle this.”
“Should we wager on it, then?” Neito asked, that same insufferable drawl making Katsuki’s skin feel too small for his body. “Who’ll come out on top, as it were?”
“I will,” Katsuki told him, stretching his arms over his head and rolling his neck. Neito just snorted.
“You know, your false confidence says so much more about you than anything else, Bakugou.”
“False my ass,” Katsuki hissed, turning to face him. Neito hadn’t even taken off his goddamn blazer, just stood there with his stupid hands in his stupid pockets and that stupid smile on his stupid face. “Fuck you.”
“Fuck me yourself, you coward.”
Katsuki moved.
He moved before his mind even gave the command, muscle memory driving him to speed up with every step until he was damn near flying at Neito who just continued to stand there as though Katsuki didn’t have the balls to hit him, to throw him down, to destroy him.
He didn’t land a hit, but he managed a grab. He’d watched Neito fighting before; his quirk wasn’t actively useful unless he could copy someone else’s, so he’d been one of the students Aizawa had pulled aside to train in hand to hand combat techniques some weeks. Katsuki knew, logically, that Neito was using his own weight and speed against him, but that didn’t stop him yanking the guy close and rolling both of them across the cold cement until they landed hard against one of the smooth, flat walls.
The wind was knocked out of them both, and the sound Neito made as he tried to free himself of Katsuki’s hold did something to the angry, agile, primal part of Katsuki’s brain, so he grabbed his hair and shoved him harder against the floor and pinned him with his weight.
“Fine,” he breathed.
And then he bit him.
He bit his way into Neito’s mouth until his lips parted in surprise and then he licked his way deeper, pushing and pressing and holding him still as Katsuki asserted himself in this new territory.
He’d expected the other Alpha to fight back, to squirm free, to act indignant and unhappy and petulant. He had not expected Neito to go damn near soft against him, submissive as anything, and kiss him back.
Bite. Bite him back. Because he’d…
Fuck it. Fuck all of it.
And fuck Neito in particular.
Katsuki felt more than heard the rumble of a purr from deep in Neito’s chest, and realized that his own body was responding similarly. Purring, a universal sound of contentment, of protection, of pleasure and comfort and not this, not what was happening here. Maybe it was a growl? Maybe he’d misheard?
But even if he’d misheard, when he yanked Neito’s legs wider to shove himself hard between them, he knew for a fact he wasn’t mistaking the sounds his own body was making. And that was a purr, loud, low, trilling once in a while into pitched little flickers of sound.
“Shit,” Neito’s voice was lower, not that irritating twang of indifference, but like sinking into a warm bath. It brought shivers up over Katsuki’s skin, and when his fingers slid into Katsuki’s hair and tugged, he allowed himself to be moved lower, dragging his nose over Neito’s scent glands.
Sharp and cool and fresh, the scent slid right into Katsuki’s blood and joined the adrenaline there, freezing its way through him until his inner Alpha howled with the desperate need to take, and claim, and possess…
“You fuckin’ bite me, and I’ll kill you,” Neito warned him, though the weight of his words was somewhat lightened by the way his breath hitched when Katsuki rubbed their clothed cocks together again.
“Like I’d wanna burden myself for life with someone who smells like a dental office,” Katsuki muttered.
“I’m your best bet, since your scent gives people cavities.”
“Do you ever shut the fuck up?” Katsuki snarled, holding himself up over Neito again, their hips still stuttering together in aching, needy ruts.
“Fuckin’ make me,” Neito spat. So Katsuki kissed him again, because that had done a good job of shutting him up last time.
But soon sucking face and rubbing one out wasn’t enough, because Neito’s scent was starting to make Katsuki dizzy in the best way, and his instincts were screaming, and Neito’s hands were demanding and needy and quick against his uniform, yanking his shirt open and scattering buttons everywhere before he set his hands to Katsuki’s nipples and twisted.
“Shit, fuck!”
Fingers were replaced with lips against one of them, and Katsuki held himself up on a shaky forearm as he fumbled with Neito’s belt before undoing his own. They might as fucking well, at this point, the energy had to go somewhere, and maybe this would be better than blowing each other up across the gym for a few hours.
Sometimes “I won’t tell if you don’t” worked better than a threat.
Katsuki keened as Neito’s tongue did something to him, and finally got his hand into his underwear and wrapped it around Neito's twitching cock.
Katsuki had never really been one to lay it out and measure, but he’d snuck glances like any hot blooded man in the locker rooms. They were about the same size, girthy and long enough to feel even if it was partway in. Not that it mattered to Katsuki, he wasn’t going to be the one feeling it.
“Nnngh put that goddamn mouth to use for a change and suck me,” Neito groaned, giving Katsuki’s nipple a particularly vicious twist before dropping both hands into his hair and shoving him down.
Katsuki shook him off like a proud yearling and glared.
“I suck you, I fuck you,” he stated. The other Alpha just shrugged, like this wasn’t a big goddamn deal. And maybe… maybe it wasn’t? Katsuki didn’t know– nor did he care– who his classmates fooled around with. Maybe Neito had had half the student population in his bed already, wasn’t any of Katsuki’s business.
With a growl that came unbidden from the depths of his inner Alpha, he ducked his head and pressed harsh kisses along Neito’s navel and down through the warm happy trail to the thatch of hair at his groin.
“If you fuckin’ knot me I’ll blow your dick off,” Katsuki promised him, and Neito groaned again, at once needy and irritated.
“Hurry up.”
With some more incoherent muttering, Katsuki wrapped his hand around the base of his cock and guided the tip into his mouth.
Katsuki had seen porn, he’d done his share of reading, he’d bought himself some toys from very shady looking online stores in preparation for his ruts that had never come. But none of that could ever compare to the power he felt rocket through him when he heard Neito’s reaction to his tongue.
“God, yes, yes, fuck!”
He sounded shattered, and all Katsuki had done was rub his rough tongue against the swollen head of his cock. So Katsuki did it again, and again, until he got used to the hefty weight on his tongue and experimentally sucked Neito a bit deeper. It pulled a sound from him that went straight to Katsuki’s cock, so he took him an inch deeper again.
Beneath him, the other Alpha was writhing, arching up, wrapping his legs around Katsuki’s head as his hands tugged his hair and soothed it down in equal measure. The way a cat pressed against a blanket over and over, content and relaxed. The purr that had hummed to life at their initial contact came back louder and deeper, a primal rumble that had Katsuki’s instincts screaming to reciprocate. So he did, the vibrations driving a jolt through Neito’s body before he let out a helpless laugh and spread his thighs wider.
“Shit you’re good at that, holy shit,” Katsuki preened, pulling off his cock to catch his breath, and stroking up the length of Neito to gather spit and precum against his fingers. When he sucked him in next, he teased a finger behind Neito’s balls, further still, until he found the quivering bud of muscle and rubbed against it.
“Katsuki, god dammit!” Neito shuddered, and in a brief moment of clarity, Katsuki moved his hand away, only to have it grabbed roughly and shoved back again. “Don’t you dare stop, I swear to fuck if you stop…”
He didn’t finish the threat, Katsuki didn’t care. He slid his finger into him hard enough to shut him up, and took his time sucking the bitter precum that leaked out of his cock at the sensation. When he felt he’d been generous enough with waiting, he started to twist it gently, feeling out the clenching heat of the other Alpha. He could feel more spit gathering at the base of Neito’s cock, against his balls, dripping down to Katsuki’s hand as he began an experimental rhythm of erratic thrusting, hoping he was doing something that felt somewhat experienced.
If it didn’t, Neito hardly seemed to care.
“Another one,” he whined, “use ano–another one.”
So Katsuki did, two fingers slipping into him and scissoring open as he continued to tease the head of Neito’s cock, as he continued to make his thighs tremble and shake around his ears. And then… Neito damn near convulsed beneath him, bending over and around Katsuki before laying flat on his back and panting, feet kicking out against the floor, hands pulling Katsuki’s hair so goddamn hard he was pretty sure he felt some follicles bid farewell to his scalp.
“Stop, stop, stopstopstop, you fucking brute get off me.”
Katsuki pulled back with a choked gasp and glared at him, but before he could speak his mind, Neito’s hand joined Katsuki’s wrapped around him and twisted, pulling the first pulse of his orgasm hot over his skin.
Katsuki stared, eyes wide and lips parted and slick. He stared as Neito’s pleasure manifested itself with hitched sobs and shuddering twitches. He stared as he realized that the Alpha had warned him off before all of that ended up in his mouth.
Something about that made Katsuki feel some sort of way, and he didn’t like it.
So as soon as the first waves had ebbed, Katsuki gathered some of the spunk against his palm and shoved his fingers back into Neito, giving him not a second’s worth of time to catch his breath.
“What–?”
“Gonna fuck you,” Katsuki muttered, glaring up at the other Alpha as though challenging him to question it. Instead, Neito’s expression was one of awe and something… softer. Before he licked his lips and swallowed, dropping his head back to the ground again.
“Yeah, you better,” he replied.
Katsuki narrowed his eyes before turning his face to nuzzle roughly against the insides of Neito’s thighs. Not quite as potent as the scent glands on his wrists or neck, the ones near his groin smelled just as sweet, just as intoxicating, and seemed to do just as a good a job at calming Katsuki’s instincts.
He added a third finger and started to purr when Neito’s breath hitched and he tensed beneath him.
He didn’t know why he was being so nice. Why he was taking his time when Neito had spat on his honor as an Alpha, had called him weak, over confident, a coward… he should have been pinning him and breaking him, leaving bite marks all over his skinny, useless form so he learned his lesson, so he didn’t try that shit again.
With anyone.
With anyone else.
Katsuki freed his hand and fumbled with his own pants as he sat back on his heels. It was only then that he got a proper look at Neito, and it took his breath away. Flushed, trembling, eyes reflecting red when he turned his head. His usually primly styled hair was a goddamn mess, his chest rose and fell quickly on voiced breaths, his cock twitched against the mess it had made on his belly.
When Neito turned to catch Katsuki’s eyes, he grinned, a feral and bright flash of elongated fangs, and Katsuki found himself grinning back.
He stroked himself a few times, already so hard it hurt to touch, before lining himself up and holding himself over Neito. It took a few tries, his hands shaking and slippery and both their bodies oversensitive and overwhelmed, but when the head of his cock caught against the rim of muscle they both groaned. And when he started to sink into the agonizingly tight heat, he whined.
The sound was returned, followed by a purr, a purr and reassuring hands in Katsuki’s hair, wandering up and down his back in soothing strokes. And it felt good. It felt so goddamn nice.
“Fuck that’s tight,” Katsuki whispered, before letting Neito nuzzle him, scent him, kiss him again. And Katsuki kissed him back.
Their coupling was just as awkward as he’d been led to believe the first couplings of any pair would be. Katsuki lasted a good few dozen thrusts before he shoved himself as deep as he could go without knotting the other Alpha and emptied into him. Both were shaking. Both were sweating. Caramel and mint mingled together with cool graphite and burning iron, a smell which should have been disgusting but that somehow worked with them.
They lay in a haze and a daze, Katsuki heavy on top of Neito, and Neito’s hands carding through his hair.
It didn’t happen with a bang, thankfully, but at some point they seemed to realize what they’d done, and peeled apart from each other to crawl some distance away and assess the situation. Neither spoke. No teasing, no banter, no snide remarks. They just… sat there, covered in each others’ mess.
“So, uh,” Katsuki cleared his throat and rubbed the back of his neck before yanking his pants closed.
“I take it back,” Neito interrupted him quietly, trying to figure out what to do with his, quite frankly, ruined uniform. He chose to shrug his shirt off and wear the blazer over his bare skin, in the end. “It’s certainly not false confidence.”
Katsuki froze, before continuing to tug his own clothes back in order. There were three buttons still dangling from his shirt. He’d need to find the others, he wasn’t sure he had any more spare in his sewing kit at home.
“Yeah?” He asked, kicking himself as soon as he did.
“And cowards don’t fuck like that,” Neito added, and Katsuki couldn’t help but snort. When he looked up, Neito was giving him that oddly soft look again, so he looked away.
“So we done? Will you stop being an asshole?”
“Certainly not,” Neito sniffed, stretching his shoulders and running his hands through his hair. In Katsuki’s eyes he looked like a feral kitten grooming himself. “If anything, I’m going to be twice as bad.”
“What the f– why?”
“If my gentle ribbing led us to this?” Neito replied, eyebrow cocked and lips quirked in a smirk. Katsuki cleared his throat and rubbed his cheek with the back of his hand.
“You wanna do it again?”
“You’re a great scratch for that itch,” Neito shrugged, nonchalant. And Katsuki felt all possible warmth towards the boy vanish in a puff of smoke. “I’m more than happy to be fuckbuddies. But I’m not your bitch. When rut hits, you find yourself an Omega like the rest of us, my body’s not built for that.”
Ruts.
Right.
Ruts that Alphas got, and Enigmas didn’t. Katsuki just hummed, before resting his weight back on his arms and staring up at the ceiling.
“What if, uh,” he licked his lips, “what if that’s not gonna be a problem?”
“What, you have a harem of Omegas already?” Neito snorted. Katsuki sucked in a breath and released it again.
“What if ruts aren’t a problem?”
“Ruts are always a problem.”
“Not if you don’t get them,” Katsuki replied tersely, and at that Neito sat quiet. Katsuki waited. For the sharp snarl of cruel teasing, for the knife to dig deep beneath his ribs. But it never came. Instead, he heard Neito shuffling a little closer til they were sitting a few feet away from each other.
“No ruts, huh?” He asked. Katsuki nodded, just once. Neito’s eyes narrowed and he made a pleased warbling noise in his throat. “Guess that means we’re about to get real friendly, huh Bakugou?”