Chapter Text
It wasn’t that Bakugou’s dynamic was a secret, per se, but rather that it wasn’t flaunted like the others tended to do.
While scent blockers were mandatory in class and during training, most students decided to forgo them in the dorms, scenting their packmates or classmates, which usually tended to be the same thing.
In a normal classroom, students might form mini-packs based on friendships, relationships, and chemistry, just like normal friend groups. As poor, sweet-suffering Aizawa would tell anyone who asked, his students were not normal, and just had to refuse to live normal lives.
(Of course, he’d say it all with a scowl and that ever-present note of worry and concern in his scent.
Really, he could pretend to be unbothered all he wanted, but every student who’d gone crying into his arms at some point or another would call him out.)
Consequently, their whole class ended up bonding as one big pack (grumpy Sensei included) in addition to the mini packs within.
Izuku, Shouto, Tenya, and Ochaco could nearly always be spotted together (and wow, Aizawa’s colleagues would remark, three alphas and one beta making up a pack? It’s a miracle they haven’t torn each other’s heads off. Aizawa took pride in his students’ self-control of their instincts, but was also endlessly exhausted by their lack thereof. A contradiction if I’ve ever seen one. It’s a miracle I haven’t torn my head off, he thought) and were often shadowed by Hitoshi.
The girls tended to stick together as well, although strangely Yuuga blended seamlessly into their pack. On second thought, maybe not so strangely, actually.
Mashirao, Mezou, Kouji, and Rikidou all gravitated towards each other, Fumikage and Yuuga occasionally joining them. Fumikage, Kouji, Tooru, and Tsuyu also got along well, and have formed some kind of bizarre craft club that meets in the kitchen after school on Fridays (much to Katsuki’s ire).
Of course, the self-proclaimed Bakusquad had formed a pack as well, extroverts Mina, Eijirou, Hanta, and Denki roping Kyouka and Fumikage into pestering (Read: befriending) Bakugou whenever possible and partaking in the stupidest activities known to man. Given that they had literally named their pack after him, one would assume that he was at the heart of it. They would be wrong.
Bakugou wore his scent blockers at all times, refused to partake in the “sappy bullshit” of scenting and cuddling with either his big or small pack, choosing to retire to his room at promptly 8 PM or sometimes even earlier, skipping out on pack bonding nights. The only people he would even remotely consider allowing to scent him and/or be scented by him were Eijirou and Izuku, and only on special occassions.
So it was easy to forget, of course, in a school full of betas and alphas, that Bakugou Katsuki was an omega.
An omega who was currently aggressively flopping eggs onto 20 serving plates and glaring at anyone who dared to even look at him for a moment too long.
Naturally, Class 1-A lost their shit.
“So he really does love us,” Denki’s eyes watered dramatically as he clutched his silk pajama shirt from his spot on the couch, having freshly learned his lesson to not question Bakugou’s kindness close-up lest he decide to incinerate it and smack you across the face with the ashes before forcing you to eat them. Eijirou was not much better.
“Bro,” he paused, lower lip wobbling. “Bro. This is so manly.”
Hitoshi looked around, pinched himself, then looked around again, eyes locked on the clock on the common room wall. “This cannot be real.” Multiple murmurs of agreement sounded.
Ochaco had the briefest, passing thought of Bakugou being cute, and then went silent on the couch like she was afraid he would read her mind and kill her.
Deku seemed to be the only one not freaking out. At least, not how the rest of the class was. A pleased and excited foresty scent emanated from his glands as he smiled, the smile he smiled only for hero merch, and sighed blissfully, eyes closed. “Kacchan gets so cute when he’s in preheat, doesn’t he?”
He opened them to be met with 18 wide eyes and a dozen hanging jaws. He chuckled bashfully, scratching the back of his neck. “Right. You guys aren’t… familiar, with this side of Kacchan.”
“No shit,” Mina urged, “Last night he almost killed us for talking too loud on a Friday night after skipping our pack sleepover, and on Tuesday I thought he was going to put Denki’s head in the food processor for even asking him to cook for anyone else. Now you wanna tell me he’s making breakfast for all of us? What the actual fuck??”
Tenya, too bewildered to even pretend to care about her cursing, nodded rapidly in agreement, chopping his hand, opening his mouth, and then closing it intelligently before immediately chopping again. It took everything in Deku not to giggle at him.
“Kacchan getting more violent is also a side effect of his preheat.” Also his regular heat, Deku didn’t say, fear crawling up his spine rather nostalgically. He remembered the first time he’d tried to check on Kacchan during his heat, he almost brought the ceiling fan down with how big he was sparking off. “Mainly, though, he gets super motherly and sweet and cute and soft and touchy and—“ he quickly snapped his mouth shut, eyeing the kitchen. Thank All Might Kacchan didn’t hear him. “…He takes care of people a lot more, I mean.”
Kouji stared at the kitchen with all the fear of a soldier being drafted off to war, internally crying at Izuku’s inability to just stop talking as he continued. “I mean, I always know when his heats are coming since my ruts tend to come right after or sometimes even during, but it still takes me by surprise whenever he shows his softer side like this.” He took a big, obnoxious sniff of the air, a twinge of disappointment coloring his scent. “I hope he takes off the scent patches soon. He smells so good like this…”
”You— Your heats and ruts are synced?” Momo gathered the courage to ask, leaning in inquisitively. “But you two aren’t— I mean, that’s not really…” Proper, she doesn’t need to say. She knew they mostly, presumably, got over whatever the fuck was always between them and have gotten closer over the last two months, but surely that wasn’t enough time to mate, or even fully form a bond that deep.
For an alpha and omega to have their cycles synced, they’d have to mate and mark each other or form a deep emotional bond, their inner alpha and omega reaching out to their bodies to ensure that they could spent their heat and rut with each other optimally for the best chances of producing offspring. The omega would go into heat and be aided by their alpha, and just as they came out of it, exhausted and facing hormonal drops that leave them emotionally sensitive and physically vulnerable, their alpha would go into rut and feel intense urges to take care of, protect, and pamper them, but most importantly, breed them. The omega staying with the alpha during their rut would (—ideally, but unfortunately not always—) guarantee their safety and fulfill the alpha’s urges, as well as help form an emotional bond between them that would give way to intimacy and therefore reproduction. These types of synced cycles were unlikely to get male omegas pregnant, as many were infertile or close to it, but on occasion synced cycles would occur at exactly the same time and boost the omega’s fertility as well as heighten both partners’ instincts and urges, making for what would be a catastrophic disaster in high school, especially a high school like UA where both parties would be looking to make a name for themselves in the extremely dangerous and competitive world of professional heroism.
If their cycles were to sync like this… if they’d already been engaging in intercourse with each other during their cycles to create this bond—
“No, we’re not.” Izuku waved a hand flippantly. “We’ve just known each other since we were little. Never really separated so we just kind of ended up syncing up, you know?”
Tenya and Momo breathed out some of the largest sighs of relief they’ve ever had the pleasure of exhaling before Bakugou shouted from the kitchen.
“HEY, FUCKERS! BREAKFAST’S READY!”
Hanta might’ve drooled all the water out of his body if he didn’t immediately start digging in, earning a scoff from Bakugou, which he replied to by making an unintelligible noise with his mouth full and giving an extremely affirmative thumbs-up, face buried in his plate.
He’d made them all eggs, sausages, toast, and pancakes— a classic American breakfast spread. The eggs and sausages were all on disposable plates that he’d labelled with each of his packmates’ names, egg and sausage preferences perfectly accurate for each person. Scrambled eggs and turkey sausage for Ochaco, sunny side up and beef sausage for Eijirou, air for Hanta because he’d already devoured everything on his plate and begun reaching for pancakes and toast from the big plates in the center of the island, an omelette and classic sausage for Denki… Where did he even learn this? Not even Deku knew his classmates’ preferences this well.
He let pride flood his scent and preened when he caught a whiff of satisfaction and pride and good omega, alpha approves leaking out from under Bakugou’s scent patch.
Shouto barely frowned past his usual morning pretty boy R.B.F. and picked at his turkey sausage and omelette with his fork. “No soba?”
In retrospect, it was meant to be a joke. All of his classmates recognized and understood it as a joke. His stupid preheat hormones were just getting to his brain and fucking it up. Hell, even Shouto’s signature chilly scent was light and pleased, like sun reflecting on the snow, but… Katsuki couldn’t help the disappointment clearing out and replacing his happy, warm scent in the kitchen, the irritated growl he tried to release coming out as more of a quiet whine. All eyes zeroed in on him immediately and all it did was make his face flush as he tried to come up with something smart to say.
“No manners?” Which really wasn’t a good insult considering he’d just called them all fuckers instead of just declaring that breakfast was ready like a normal, good omega who could be nice to his pack without feeling awkward and uncomfortable and scent them and cuddle them and—
Deku was on him in an instant.
“Hey,” he murmured, quiet but stark in the kitchen’s silence. “You did great. Shouto’s just teasing. He doesn’t mean anything by it.” Rubbing his wrist against Katsuki’s before moving it to his neck, right where a claiming bite would be. Infusing the gland with his scent, he turned to Shouto and asked, only a bit aggressively: “Right, Shouto?”
Shouto, regretful and for once getting the memo, nodded firmly. “Mn. I like this too. You’re a great cook, so everything you make is on par with other people’s soba.” He pushed the pleased note in his scent farther, only stopping when he saw Bakugou’s shoulders relax minutely.
“Why don’t we scent Shouto?” Deku suggested, causing said alpha to jump about three feet in his chair. He had no problem with scenting Bakugou, they were closer with each other than a lot of their classmates, but he was pretty sure he’d kill him if he dared to even bring it up. Imagine his surprise when Bakugou nodded reluctantly, allowing Izuku to take his wrist and offer it to Shouto across the table, watching closely.
Shouto blinked, and the slightly predatory haze to Izuku’s eyes remained. “Can I scent you, Bakugou?”
“Yeah,” he replied, a little breathily. The distance his wrist had to travel over the large countertop forced him to bend over it minutely, Izuku so close to his side that his right thigh bracketed Katsuki’s left one against the island. He was not touching that with a ten-foot pole, but he’d be happy to scent Bakugou, so he did.
Bakugou’s shoulders completely slumped, his eyes almost half-lidded as Todoroki rubbed his scent gland against his own, happy scent and a little chirp he wasn’t even aware of escaping his body. The room smelled like proud and pleased omega again and everyone basked in it, especially Izuku, who gently grabbed his wrist and dragged it away once he’d stopped actively rubbing it against Shouto’s own. He made eye contact with the class, all gathered around the island. “Food’s gonna get cold, let’s eat— everyone say thank you Kacchan!”
Everyone did not, in fact, say thank you Kacchan. They said thank you Bakugou, which worked just as well.
(Denki did say thank you Kacchan, though, and got thoroughly cursed out.)