Two weeks after the Sludge Villain incident, just as media coverage of the event was winding down, Kacchan disappeared.
Considering how he and the blonde seemed to have entered a state of mutual avoidance, it took Izuku longer than he cared to admit to realize the young alpha wasn’t simply home, brought down by a cold or something equally mundane. He didn’t know, until a couple of police officers came to their school, inquiring when anyone had last seen Kacchan.
Izuku, of course, panicked.
“This isn’t a runaway scenario,” he insisted that afternoon, even while lugging a burnt-out microwave across the beach. “Kacchan wouldn’t go anywhere on his own! Someone’s taken him!”
All Might, at least, seemed to listen, even when the police had not. “I have a friend who might be able to look in on the investigation, my boy - I’m sure they’ll find young Bakugou in no time.”
Izuku nodded. And still made his own plans to investigate.
For the following three days, his early morning jogs went along various routes, through different neighborhoods, exploring places Kacchan might have disappeared from. The police had mentioned he’d gone missing on the walk to school, giving the perpetrators nearly a whole day’s lead, as the teachers assumed he’d stayed home while his parents didn’t expect to see him again until dinner. In the week since, there was no telling how far Kacchan had been taken.
There was no telling if he was even still alive.
Despite the years of distance and rough interactions, Izuku’s heart still clenched painfully at the thought of Kacchan being, just, gone. The first time it had occurred to him the alpha boy might be dead, Izuku needed to sit down for a good five minutes just to focus on getting his breathing under control.
Kacchan needed to be found. He had to be alright, he was going to come home.
These were the thoughts Izuku repeated on loop as he poked through the alley behind a bunch of closed shops in the pre-dawn hours one morning, a bit removed from Kacchan’s usual route to school but close enough to warrant checking. He’ll be alright, I’m going to find him, he’ll be alright, I’m going to find him-
“Find who, kid?”
Broken out of his fervor, and wincing at the realization he’d been mumbling out loud again, Izuku turned to explain. And stalled out when he realized four large men had surrounded him.
“The fuck is this?” He pointedly asked.
“Little punk was poking around where he shouldn’t have been,” one of the men sneered, grabbing a fistful of green hair and twisting the kid’s head back, making him cry out. “Suisoku said he’s looking for that alpha brat.”
After a glance at another of the shift members, whose Quirk meant he never guessed wrong, Gado stood up to approach them. The boy met his gaze as he came - scared, bewildered, pleading. Gado felt for him, he did, but fear of his boss’s reaction out-weighed any inclination to turn the kid loose. Besides, there was a whiff of something in the boy’s scent that stood out even to his under-developed nose.
“Omega?” He asked, looking to Suisoku.
The other man nodded. “Only reason we brought him down. Would’ve been simpler to kill him - but the boss did say it was about time to introduce an omega to the experiment, right?”
Nodding, Gado looked the kid up and down once more. “That she did... well, let’s see what we’ve got here, then.” And with that, he touched a fingertip to the kid’s forehead. Age, name, genders primary and secondary, height, weight, and a few other details flashed into Gado’s mind. What stood out to him, though, was the note of No Quirk.
“Hm. That’ll make things interesting.”
He waved off the inquiry, before turning to head deeper into the underground facility. “I’ll ask the boss for her approval, but - go ahead and get him stripped down, regardless.” As he walked off, Gado heard a yelp and the sounds of a brief struggle as the men began their task, the boy clearly unhappy with such a turn of events. He shook his head. Kid would be in for much worse than that, soon enough.
The guard holding his shoulder in a bruising grip suddenly stopped, the abrupt halt nearly tripping Izuku up. He managed to bite back his instinctive yelp, at least. Warily, he watched the man punch a code into a little screen set in the wall of the hallway, triggering a door to slide open in front of them.
“In you get,” another guard said, shoving him. Izuku did yelp when he fell through, tumbling down the couple of steps to a cold metal floor. The door slid shut again before he even had time to sit up and groan.
Shivering again, the boy stood to look around his new surroundings.
At his back was the wall he’d come through, made of the same dull grey plating as the floor and ceiling. In the center of the room was a rectangular indentation in the floor, covered with padding at the bottom and big enough to lay down in. Across from him, a single pane of glass made up the far wall, looking out onto a walkway that made Izuku think of zoo exhibits. To either side were cells identical to his, visible through clear partitions in the center of the walls. The one to Izuku’s left was empty; the one to his right...
“Kacchan,” he whispered, stumbling closer. “Kacchan!”
Evidently, the materials separating them were soundproof, as the other boy didn’t so much as stir where he was curled up on his cell’s bedding. Kacchan too had been stripped down to just his boxer briefs, but he didn’t seem hurt, which eased something inside of Izuku’s chest. Tears welled up in his eyes, but Izuku hastily scrubbed them away, and tried banging his fist against the partition. It made a solid-sounding thud, and that was enough to make Kacchan’s eyes snap open.
Furious eyes which locked onto Izuku’s horrified gaze in an instant.
Kacchan snarled, baring his teeth, and then he was up and attacking the partition. Izuku fell back with a startled cry. Even as he recoiled, though, his mind was cataloging everything wrong with the alpha.
The most obvious, first and foremost, was a lack of explosions, not even a hint of a spark launching from the boy’s palms. Beyond that, though, was the way Kacchan moved - attacking instinctively, the movements fast but unplanned, unrelated to one another. His hands were held as if he wielded claws instead of fingernails, his shoulders raised in such a way to make himself seem bigger.
Kacchan was- he seemed almost animalistic. Feral, even. It scared Izuku more than anything else the alpha had ever done to intimidate him.
“Ah, good, both Subjects are already awake.”
The voice made Izuku jump, and he looked to the glass wall. A group of people stood on the other side: two of the guards from before, plus the one who’d touched his forehead, along with a few people in long white lab coats with clipboards in their hands. At the front stood woman with burnt orange hair and glasses who seemed to be in charge.
As soon as Kacchan spotted them, his snarl grew wider, and he changed targets to the front of his own cell, ferociously clawing to try and get at the woman.
“Note that Subject A-4’s aggression levels remain unchanged,” she said. Izuku couldn’t actually hear the words as she spoke them; rather, they came through a speaker in the ceiling after a few seconds of delay.
Even so, he faced and addressed her through the glass. “Who are you? What did you do to Kacchan? What is this place?” All of Izuku’s questions were ignored, unfortunately. He tried to put on a brave face, but didn’t feel like it was very successful.
“Hypothesis for today’s test states that Subject A-4’s hostility will be curbed by the introduction of Subject O-4. Note that the introduction of an Omega element is two days ahead of schedule, but an allowance has been made based on how rapidly Subject A-4 reverted to purely Alpha behaviors, far exceeding expectations.”
Izuku felt something cold take hold of his insides and squeeze.
He tried to protest - tried to tell them how much Kacchan hated him, how reducing the alpha to primal instinct alone would not make him more inclined to tolerate Izuku’s presence. He approached the glass, trying to make eye contact with any of the adults on the other side, begging for them to just listen, please! But none met his tearful gaze for long, and after a while Izuku realized they probably couldn’t hear him, either.
“Additionally, to avoid complications due to his Quirkless nature, Subject O-4 will remain uninfluenced from Chemical O during the course of the tests - a control, to see if the regression process can in fact occur unaided.” As soon as she was finished speaking, the woman with glasses pulled a remote control out of her pocket, and pressed two buttons. “Begin introductory test.”
Behind Izuku, the partition separating him and Kacchan slid aside.
He wasn’t even sure how long it had been; time got kinda foggy when one couldn’t see the sky, or a clock, or anything else that might be used to mark the passage of time. Meals showed up when he slept, and Kastuki couldn’t say if they arrived on a regular timetable or not.
Granted, he couldn’t say a lot, period.
There was something the assholes who’d imprisoned him kept pumping into the cell on and off, something that smelled worse and worse every time he had to breathe it in. A little voice in the back of his head said it was because his sense of smell was getting stronger with each dose, but Katsuki had a hard time listening. Words didn’t seem to matter quite so much anymore, whether they were coming from his own head or the assholes who kept watching him. As far as he was concerned, the world had gotten a lot simpler since he’d been brought here:
Weird scents, bad. People on the other side of the invisible barrier, bad. Lack of pack, very bad.
In short, it was a shitty situation all the way around.
And then something changed.
He was woken up by a thud, something new, something annoying. A face on the other side of the barrier - he reacted as he always did, snarling, growling, warning. It didn’t occur to him at first that this was different from the usual, that the person on the other side was reacting to him, unlike the other assholes.
When said assholes actually showed up, Katsuki immediately had to go scream at them instead, seeking to chase them off, to get through the invisible barrier and show them just how bad an idea it was to lock up a badass alpha like him-
A new sound reached his ears. A new scent tickled into his nose.
Pausing, Katsuki looked over his shoulder, and saw that the other barrier was gone. Baring his teeth in a fierce grin, he stalked over to the empty opening, peered through it - and was hit by a wave of intense fear-panic-terror.
Part of him wanted to preen in the face of, finally, an appropriate reaction to his presence. Another part overshadowed it, though, caught up in the knowledge of just what, who, that emotion-heavy scent was coming from.
Deku, the voice at the back of his head whispered. Growling, Katsuki glared as the omega stopped his yelling and whirled around to face him.
“K-kacchan,” Deku stammered. Katsuki darted towards him, causing the other boy to flinch. Bony arms were thrown up to shield his face, green eyes squeezed shut. “Wait, Kacchan, please don’t-!”
Katsuki wrapped his arms around the omega, buried his nose in fluffy green hair, and simply breathed.
Disconnected thoughts swirled around his head, accompanied by a contentedness he wasn’t used to feeling. His omega, his packmate, here, keep him close, keep him safe, must keep the omega safe.
There was a noise of surprise below him. “Um. W-what...?” Deku started to squirm, and Katsuki growled lightly, a warning to hold still. The omega immediately froze, but his scent erupted into a new burst of uneasy fear. Huffing, because the idiot didn’t need to be scared of him, Katsuki pulled the both of them back through the opening to the farthest corner of his cell. He sat and yanked Deku down into his lap, curled up around him as much as possible, and tried to rumble in a soothing way.
Apparently it worked, because the omega stopped trembling and gradually relaxed. He even squeaked when Katsuki nosed at his neck, where he could smell the scent glands lying dormant under Deku’s freckled skin.
“Kacchan, that t-tickles.” A hand pushed at his face, and Katsuki reluctantly left off his search in order to nuzzle into the touch. “O-oh. Um. K-kacchan?” Opening his eyes again, he met Deku’s worried gaze. “Are you still- you, in there? Do- do you know that, it’s me? I just, they said you’re, you’re running on instinct now, but I don’t- is that, why-?”
Growling slightly, Katsuki brought up a hand to shove at the back of the omega’s head. Stupid nerd. He opened his mouth, coughed, and through the haze filling most of his head forced out a single word: “De-ku.”
And just like that, the omega’s face lit up. His green eyes got impossibly wide, and Katsuki felt something warm settle inside, like a missing puzzle piece clicked back into place.
He knew this wasn’t normal for them, not anymore. But the complicated mix of emotion and memory and status quo weren’t important when Katsuki couldn’t even think in complete sentences - all that mattered was that his oldest packmate, his omega, was next to him again.
Katsuki’s inner alpha purred at finally being able to breathe in the other’s scent without anything getting in the way, at being able to wrap Deku in his arms without worry. Too long he’d spent pushing the other boy away, pushing him down, but that was the past. This was the present.
Deku was his and his only.
Not only did the alpha try to avoid hurting or scaring him, he was actually gentle, tugging Izuku into corners or down onto his bedding in order to cuddle. And oh, the smaller boy might have been startled out of his wits by that first unexpected hug, but he wouldn’t struggle against the continued affection for anything: Kacchan was warm.
“I wonder if they know how unfair this is,” Izuku mumbled at one point. “Clearly, taking away your clothes didn’t have much of an effect, considering your higher body temperature even when your Quirk isn’t working, but I don’t have that advantage and so removing my clothes is practically guaranteeing I’ll want to be close to you-” Kacchan pinched his arm, and Izuku’s rant was cut off with a yelp.
Odd lack of speech aside, the alpha clearly still didn’t appreciate the mumbling. Izuku found that reassuring, in a way, that some part of the other boy remained unchanged.
What wasn’t reassuring was how Kacchan always, always snarled at anyone who observed them through the glass wall, turning to keep himself in between their eyes and Izuku. Endearing, perhaps, but not reassuring, not with how Izuku’s heart always pounded in those moments, and his breath came out in scared, shallow gasps until Kacchan noticed, and focused solely on nuzzling their faces together until the panic passed.
The worst, though, were the times that Kacchan had to be re-dosed with something called Chemical A, and Izuku was yanked away from him by the guards, shoved back into his original cell with the partition sealed shut. It broke his heart to see the alpha throwing himself at the barrier between them, expression torn between desperation and fury as he tried to get through. Izuku couldn’t understand what seemed to scare Kacchan so badly when they were separated, but even he felt bone-deep relief when the gas pumped into the other boy’s cell finally dispersed, and the partition slid aside again, allowing Kacchan to charge past and grab him in a fierce embrace.
“I don’t get you,” Izuku whispered when they were cuddling again, left alone after the third such re-dosing. “All these years you’ve spent pushing me away, like I was nothing, but now you’re hurting yourself to try and get me back when they pull me away...” He gently rubbed at Kacchan’s hands, red and bruised from where he’d clawed at the partition earlier.
The blonde rumbled, a sound that managed to put Izuku at ease, like it was one of the lullabies his mother used to hum when he was younger. He closed his eyes with a sigh, letting Kacchan nose through his hair again. Whatever the alpha was able to smell seemed to calm him as much as the rumbling did for Izuku - and whatever comfort he could offer Kacchan in this nightmarish setting, he would.
“They are the youngest we’ve ever attempted to perform the tests with,” one of her colleagues pointed out. “I doubt either one’s had any sort of encounter more intimate than a brief kiss before - plus, we’re abstaining from adding Chemical O to the equation...”
“Even so,” Zankoku said. “Subject A-4 is to date the most aggressive alpha we’ve taken readings from. With how quickly the omega took to being sheltered by him, something should have happened by now.” Inside the cell, both her subjects were asleep, curled up with one another as per usual. Monitors around the perimeter of the window displayed footage from the cell’s security cameras, along with data such as remotely scanned vitals, allowing her to fully study every aspect of the pair. One hostile, aggressive alpha with no proper outlet for his emotions, and one meek, subservient omega completely obedient to his unspoken orders... it should have been a perfect equation, following the same pattern as the rest of her previous experiments.
Instead, they’d practically dived headlong into the emotional intimacy stage, far faster than any adult subjects, and refused to advance any further. If Zankoku were any less of a scientist, she’d call it infuriating.
“Are you going to put in an order for the aphrodisiac agent to be introduced?” Her colleague asked hesitantly.
“Mm... Yes. A small dose, I think, to see what happens. Perhaps later we’ll take more drastic measures, to make sure they’re far enough along for when we introduce a Beta to the dynamic.”
“Of course. When shall I give the order?”
Zankoku allowed herself a slight smirk, still watching the sleeping subjects. “No time like the present. Let them wake up feeling the effects; perhaps they’ll assume what happens afterward was of their own inclination, and their inhibitions will be lower in the future.”
Deku started to stir about the time he was running a thumb across the dip of the omega’s spine, and he let out a happy little mumble. Katsuki let his hand drift lower, over the cloth covering Deku’s butt, and gave a curious squeeze. Frowning, because the freckled skin was much nicer to touch, he slipped his fingers underneath instead. There was no particular motivation to do so, beyond the simple fact that it felt good.
But apparently Deku didn’t agree.
The omega sat bolt upright, snapping awake in an instant to stare at Katsuki, with the unfortunate consequence of knocking the alpha’s hand away. Huffing, he changed targets to rub his palm up the inside of Deku’s thigh - and regretted it an instant later, when the omega squeaked and scrambled away from him.
“W-what are you d-d-doing, Kacchan?” Making a discontent noise in the back of his throat, Katsuki rolled onto his feet to step after Deku, who continued to back up until he was wedged into a corner. Intent on touching his red-faced omega again, Katsuki kept following. The heat in his gut was doing things to him. The clothing around his own groin was starting to feel uncomfortably tight. Touching Deku seemed the obvious answer, especially since he could smell a similar something in the other's scent, too.
But when he tried to reach forward, to hold his omega close and explore his skin further, Deku flinched. His scent took an abrupt nosedive into fear, and he started to cry.
As focused as he was on the here and now, part of him could still recall from Before, when other things had been important, when making Deku cry was something to be ignored, and the guilt of doing so went unrecognized, unacknowledged. But with the way his mind worked at the moment, such a thing couldn’t be allowed to stand.
Crooning, Katsuki dropped to his knees, hovering but not looming over his omega. His hands he kept on the floor, in plain sight, and the urges to touch that had pushed him to this point were firmly ignored. It took time, long minutes filled with Deku’s unhappy tears that Katsuki longed to wipe away, but eventually, the omega shuddered and reached for him. In an instant, Katsuki scooped him up, holding the other close and continuing to croon. He rubbed his chin and the scent marker underneath it over Deku’s head and up and down his neck, but kept his hands firmly in place where they looped around the omega’s back.
My omega, my packmate, mine mine mine.
Deku, for his part, kept sniffling for a while, his body tense and a sour undertone of apprehension permeating his scent. Eventually he eased up a bit, even nosed at Katsuki’s own neck, but still the fear remained.
“Please don’t do that again, Kacchan,” he mumbled at one point, green eyes meeting red. “I don’t know what happened, but- but we can’t, do that, okay? I don’t care how, how instinctive you get, just, don’t. Okay?”
Katsuki rumbled, and Deku slumped against him, practically boneless with relief.
He wasn’t sure what had happened either, though the little voice at the back of his head was yelling about the asshole bastards and their stupid weird scents again. Picking his head up, Katsuki took in a big sniff. Something lingered in the air, too weak for him to identify, but clearly out of the ordinary. He scowled, ticked off that a scent had caused- whatever it was that had just taken place.
Unfortunately, they didn’t have long to recover before the door in the back wall opened, and three of the assholes in grey and blue stepped through.
Snarling, Katsuki shoved Deku back into the corner, and crouched in front of him even as gloved hands started to reach for them both. These fuckers thought they could take away his omega, and every fiber of his being screamed at Katsuki to fight them the fuck off. Clawing, kicking, biting, he did everything he could - but in the end, they still managed to get him on the floor in a headlock, arms pinned behind his back. Deku was yelling at them, crying out for Katsuki as the third guard hauled him off to the other room-
-except they weren’t headed for the other room, they were taking Deku out the back door, away from Katsuki entirely. He shrieked in rage, re-doubling his efforts to get loose, to chase the third bastard down and bring Deku back-!
He could still hear the omega crying for him from beyond the door, and when the assholes holding him down let go to hurry out, Katsuki leaped around them, desperate to get there first-
Something crackled as it hit him in the chest, and pain erupted throughout his body.
Katsuki blacked out before he’d even hit the floor.
Story of my life, the boy thought to himself. Even if he’d wanted to say so out loud, though, it wasn’t exactly an option, considering the heavy metal gag clamped around the bottom half of his head.
“Which is to say, the good Doctor’s compounds were designed to have a two-fold effect: negating the Quirks of those who breathe them, as well as limiting cognitive function to allow one’s hindbrain, their animal instinct, to take charge again. De-evolution, if you will; a perfect way to make dangerous minds harmless, as well as provide scientists a way to study what humanity must have been like in ancient times.” There was a stinging sensation as the blue fluid disappeared into Izuku’s arm, and he flinched. The man just grinned, reaching up a hand to pat him on the head. “You already being a throwback without a Quirk, well, there’s no telling what side effects Chemical O would cause... which might be interesting to observe later, but for now you’ve been designated an unaltered control subject. So, you get to enjoy this stuff instead, which will hopefully get you to stop being such a prude.”
Izuku stared at him, eyes wide.
“Oh don’t look at me like that - part of the testing is to monitor what happens when subjects go into heats and ruts, but in order to get the hormones pumping for that to occur, you need to actually be getting frisky in the first place.”
At that, Izuku shuddered. Glad as he’d been earlier that Kacchan had gotten the hint and stopped his, er, advances... their captors clearly intended to intervene, and force the two of them into being intimate.
Part of Izuku couldn’t help but tingle at the thought of being that way with Kacchan, arguably even closer than when they cuddled. But overall, he felt horrified, disgusted that it wouldn’t be solely their choice, that others were meddling with their bodies and would be treating the whole thing as a science experiment.
The stinging in his arm gradually faded, replaced by an overwhelming warmth that spread through Izuku’s entire body. He felt his limbs grow weak, and try as he might the boy couldn’t keep his head from tipping over.
“There we go! Hopefully your boyfriend won’t be so hesitant this time; he’s getting a special dosing of his own, you know! Should keep those pesky higher brain functions firmly locked down so he doesn’t second-guess himself.”
I don’t think that’s it, Izuku thought vaguely, as the guards unbound him from the chair and dragged him out of the lab. He stopped because of me. But if I don’t ask him to stop, if I CAN’T ask him to stop...
He barely noticed when they came to a halt, or when the guards unlocked the gag from his head. What he did notice was being thrown through a doorway, to land in an uncomfortable sprawl on the floor. Izuku whimpered as the door slid shut, and tried without success to push himself upright.
Distantly, he heard an answering keen. When the boy managed to roll his head enough to at least see the opening between cells, it was just in time to witness Kacchan dragging himself through. The alpha had one hand pressed against an angry red spot on his chest, the other holding him up against the wall as he staggered along.
“K-” Izuku coughed. “K-kah...” He couldn’t manage to get a second syllable out, resorting instead to a pathetic whine.
Kacchan rumbled, moving a bit faster. The alpha collapsed to his knees as soon as he took a step away from the wall, but then he crawled the rest of the way to Izuku’s side. Neither of them had the energy or ability to move from that spot, so there they stayed, curled into one another, taking what comfort they could from the other’s presence.
At one point, Kacchan pressed his nose to Izuku’s neck... and then followed up by pressing his lips to the same spot. Unable to do much else, Izuku whined again. Kacchan either didn’t notice, or didn’t care, because he did it again, and then he kissed Izuku’s jaw, and then his cheek, and then his lips.
It- it felt nice, admittedly. Izuku didn’t think he could be faulted for tilting his head, just a tad, to meet Kacchan’s lips a little more evenly. The alpha even rumbled, and rubbed their noses together before kissing him again. They did it a few more times, opening their mouths after a while, Kacchan getting bolder the further they went. He brought a hand up to wind into Izuku’s hair, grabbing and tugging to better adjust the angle of the other’s head. Too lethargic to resist, Izuku went along with it.
But then Kacchan smoothed his other hand across Izuku’s chest, and- and nothing. Izuku didn’t tremble, didn’t flinch away. He wanted to, he knew he should, in order to stop the alpha from going any further. But no matter what commands his mind tried to give, his body didn’t obey.
Kacchan’s fingers traced across his chest, down his side, thumbed at the smooth skin of his belly. They stopped, however, just above the band of Izuku’s underwear. The alpha pulled back from their kiss at the same time, and Izuku saw his nostrils flare.
Please, he thought, unable to say the words aloud. Please, Kacchan. Stop. Nice as the kissing was, he didn’t want to go any further, not at the whims of scientists who were trying to play god.
Above him, Kacchan shuddered.
Then, slowly, the alpha uncurled, and stood. He wobbled for a moment, but the time spent resting seemed to have restored a measure of his usual strength. Planting his feet, Kacchan bent down to grab Izuku, and carefully pulled the smaller boy up and over his shoulder. Gasping, he blinked rapidly, watching his limp arms dangle as Kacchan walked them, step by cautious step, to the bedding inset in the floor.
Once there, the alpha sank down with a groan, and dropped his passenger onto the padded material before flopping on top of him. Izuku would’ve sputtered if he could.
Clearly exhausted, Kacchan just closed his eyes with a muted rumble. At that point, there wasn’t anything Izuku could do but smile and follow suit.
“We’ll see if there’s more activity when they wake up again,” she answered, before turning slightly to meet his gaze. “Now then - you said your men have located a suitable beta?”
“Yes ma’am - quiet little thing, but with a spine of steel when you get her ire up. Should balance between those two just fine.”
“And she’s not from the same school district as them, correct?”
Gado felt hard pressed not to smirk at that - convenient as it had been for the omega boy to practically fall into their laps, he knew the doctor was feeling more and more put out by how unconventional he and the alpha brat were being. “Of course, ma’am. I promise you, neither of these boys have ever even heard of Uraraka Ochako.”