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i live for you, i long for you

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i - compliments

“Hey Kacchan, do you like my outfit?”

Izuku stepped out of his room with a little more grace than normal, which Katsuki could hear by the gentle pitter patter of his feet on the hardwood of their apartment. Not his usual shuffle. (Katsuki would like to ignore the fact that he knew what Izuku’s fucking footsteps sounded like).

He turned from his spot at their kitchen counter and - oh god.

Izuku was wearing the widest collar of a white shirt he could have possibly found, exposing his long neck and showing a bit of pec. The shirt was flowy and long sleeved, making him look gently debauched (or maybe that was just Katsuki’s pervy brain thinking that). The shirt was long enough to cover his ass, which was a shame in Katsuki’s opinion because Izuku had on tight, thin, black cotton leggings, which would not be as big of a deal if Izuku wasn’t so fucking swole, with the sculpted muscles in his legs pulling the fabric tight enough to be nearly translucent. 

How the fuck he was managing to look dainty and hot at the same time, Katsuki didn’t know, but he figured it could hardly be fair.

“The hell are you asking me for, nerd?” he grunted out, trying inwardly to stop his stupid alpha from screaming at him to fucking kiss him already, you moron. Izuku bit his lip ever so slightly, and Katsuki feels his fingers clench on his mug of tea.

“Well, Kacchan’s amazing, and you know about fashion…? Ochako and I are going to karaoke tonight, and I didn’t want to overdress, or underdress, and you always look really good - I mean! Fashionable and your outfits are always well put together and-!”

Katsuki crossed the kitchen space at that time and put a hand over Izuku’s mouth. “Deku. Shut up.” He would deny the slight blush he felt dusting his own cheeks at the words you always look really good until the day he died.

Izuku laughed softly. “Sorry, I know that irritates you when I say those things - but they’re true!”

He shifted his balance on his feet, and Katsuki tried to make his stupid heart slow back down to a normal pace. He busied his hands with holding the mug of tea he had been making himself, and took a deeper breath than normal. Big green eyes were still peering at him, and he let out a sigh.


It was dismissive, but scores better than what he might have said years ago. They had come a long way from when he used to bully the nerd back in middle school, from friends later in high school, to hero partners and roommates in their shared apartment as adults. There was a part of Katsuki that had never thought he’d be able to have this, or anything even close to this, and looking at Izuku made his chest clench.

He moved back to the counter, their shared counter, and tried to calm his stupid, alpha heart from where it was hammering at his chest. Izuku had been so close. 

Secretly, of course, Katsuki couldn’t help but want for more, but. He’d been such an asshole. He knew Izuku would never be able to see him that way, they both had to know Katsuki wasn’t worthy.

“So? Thoughts?” Izuku prodded, somehow managing to be cute and hot and endearing all at once. Katsuki was looking down at the counter, but could hear more of the gentle sound of Izuku’s feet on the floor padding closer to him. He looked up, and suddenly Izuku was right back in his space, smiling softly, looking a little unsure. Fuck. 

It was really a simple outfit. Izuku wasn’t even wearing shoes yet. But Katsuki was dick whipped, and he knew Izuku could wear a fucking garbage bag and look hot.

“You look - it’s good. It’s a good outfit,” he spluttered, malfunctioning this close to Izuku’s soft look. God, he could take the determined looks, the angry looks, everything that came usually when working together. He could even take sparring and landing on top of each other, wrestling and fighting with skin on skin contact and heaving breaths. But this? The gentle, domestic ease? Fuck him, it was hitting hard.

Something in the air between them shifted, and Katsuki could feel a bit of a flush rising on his cheeks. In the back of Izuku’s eyes, Katsuki thought he almost saw a flash of blue, but - no. A subtle scent wafted into the air, the distinct note of pleased omega hitting Katsuki’s nose, but also intertwined with… something else. Katsuki couldn’t quite place it, but he felt stirring in his pants, and embers coiling in his stomach. He tensed, and the blue was back in Izuku’s eyes, hiding in flashes like a weird game of hide and go seek.

The moment passed, though, and Izuku let out a small laugh. 

“Thanks, Kacchan! It’s always more special coming from you. Well, I’m off, but I’ll be home before 1 or 2!” Izuku called, turning to leave. 

“Don’t get yourself killed out there, idiot,” Katsuki droned back, still stuck to the counter to hide his stupid lower half. What the fuck was wrong with him? 

Izuku just laughed as he closed the door behind him, leaving. Katsuki finally released his grip on the counter, and looked down at his pants in confusion. Why the fuck had he popped a boner in the middle of just talking to Izuku? Maybe it had something to do with that odd scent Izuku had released, the smell he couldn’t quite place.

Humming contemplatively, he sipped at his tea, before it hit him.

Arousal. Omega. It smelled like pre heat. 

Soon, probably in a week, Izuku was going to go into heat.

The strain on his pants strengthened, and Katsuki flared his nostrils in equal parts annoyance, bewilderment, and desire. It was going to be a long night.


ii - free space

The next day, Izuku sat him down on the couch in their living room, which led right up into the kitchen with no walls in between, and looked nervous. “I have to talk to you about something,” had been his only pointer towards what was going on, which was sending Katsuki’s instincts up the wall. 

“Deku. What the fuck is up,” he intoned dryly, after watching Izuku fiddle with the hem of his shirt for a whole minute.

Izuku was totally different like this. When they were at work at their hero agency, he slipped seamlessly into the role of pro hero. He was calm, reassuring, strong. But here, at their apartment, all those little traits he’d had since middle school came back to life. The twitching, the fumbling, and the mumbling under his breath. 

“Sorry, Kacchan,” Izuku chirped, looking sheepish. “I guess I should just tell you, it’s not that big of a deal, but…” he scratched the back of his head, tilting it to the side a little and showing his bare neck. “I won’t be at work all of next week. I’m - uh - nesting for my heat, there’s probably only, like, five days left till it hits.”

Katsuki sat there silent, not surprised. Was this not what he had smelled last night, lingering in the air after he complimented Izuku? Thinking back on it, the omega had been showing signs of being in preheat for a few days. He was a little clingier, laughing lighter, asking for affirmation (like compliments) more often. Katsuki found it too endearing to be fair.

“That’s all? Could have told me with less fucking pomp, nerd,” he chided, but no heat was in his tone. He was doing his best to come across as neutral, and not the creepy alpha beast he felt like and was disgusted by. He was always disappointed with himself when he reacted in such base animalistic ways in regards to his secondary gender, especially because he was usually able to keep a solid control over himself.

Izuku and he had known when they decided eight months before to become flatmates that it could be a little difficult, as an alpha and unclaimed omega. They simply decided to communicate openly with the other regarding heats or ruts, wherein the unaffected one would simply find a different place to crash for a week, allowing the one in their cycle more privacy. That was, at least, the reason on the surface.

Katsuki knew, however, his own personal reasoning. He knew that if he were to encounter Izuku in the prime of his heat, he wouldn’t be able to control himself. All of the years of carefully reconstructing their friendship back from dust would be broken in Katsuki’s brutish, alpha hands.

Ruts and heats usually only happened three to four times a year, more or less once every three to four months, so the pair had only had to deal with this three times previously. First, with Katsuki’s rut, which had occurred at about month two of them sharing an apartment, second, with Izuku’s heat hitting right around month four, and then about two months before the current day, with Katsuki’s rut hitting again. 

Although he was not very into his second gender, Katsuki wasn’t as shy as Izuku was about announcing his upcoming rut. He never sat the nerd down, he usually just mentioned over a meal or something that he would be in rut soon. For him, it wasn’t a big deal to tell Izuku that in t-minus four days he would be struck with a lust spell so strong he would’t be able to tell right from left, up from down. 

Izuku, however. Last time they had this conversation, he was so obviously nervous, but for another reason as well. He was more than just warning Katsuki, but also asking … permission, almost. 

The last heat Izuku had, he had spent with Shindo Yo in their apartment.

Upon remembering, Katsuki grimaced. “Does that mean I’m going to come back after next week to this place stinking of that asshole again?” he grumbled. He hated that other alpha. Well, mostly, he hated the fact that that asshole had what he wanted, what he probably would never have. That five days had been excruciating for Katsuki, knowing the omega he wanted was being helped through his heat by a different alpha.

The green haired boy’s eyes widened, and he let out a small chuckle. “Ah, no,” he confessed, looking shy again. It was a casual admission, but Katsuki felt something hot and molten slide down his spine. Oh.

“What?” he asked, voice lacking its usual heat, sounding far more interested than teasing. “It didn’t work out between you two? Guess I haven’t smelled his fucking ugly ass here lately.” He was trying to sound nonchalant, but he couldn’t deny the part of him that wanted to know, and badly.

The alpha in him was puffing his chest out, crowing in victory. It’s because he wants us, because that alpha wasn’t good enough like we are, his alpha claimed. Because only we could give it to him right .

He noticed too late the scent he was giving off, almost possessive, territorial. It should have made Izuku uncomfortable, but-

But Izuku just fluttered his eyes closed, sitting way too close to Katsuki, close enough that the blonde could see the subtle way Izuku shifted to squeeze his thighs closer together. God, he looked delicious. 

“Ah, Kacchan,” he said softly, making Katsuki’s senses go haywire. Did he know what he was doing to Katsuki? “I guess if you really want to know, he just… couldn’t… give it to me hard enough.”

Izuku’s words dropped like a weight on his chest, and Katsuki felt something shift in the air between him. His breath hitched. He wasn’t going to let himself think about the implications of that. At least, not right then. Because if he did, he might just pop a knot right there in their living room. 

“Hah? So who’s next, half and half bastard?” he said, trying to distract himself from the way Izuku slowly opened his eyes, from the way he tilted his head and let the long line of his neck show, from the heat curling in his own stomach. 

The other boy let out a small laugh, and shook his head. “No, not Shouto. Unless you- well.” He made eye contact with Katsuki, and the alpha felt something primal clawing inside him. The air felt heavy between them, and Katsuki felt himself lick his lips. “I’m not planning on having anyone else come over for my heat,” Izuku said, each word sounding very intentional. Like there was some sort of hidden meaning behind his words, if only Katsuki could find it.

Time seemed to stand still while Katsuki stared into Izuku’s eyes. The omega wasn’t backing down, almost daring Katsuki to say something. 

He wants you, idiot, make a fucking move , his alpha screamed at him, but Katsuki knew that couldn’t be true. He had been so awful to Izuku for years, he knew this was the most he could ever hope for. Together, but only in the same room. Close, but never enough to touch.

“Thanks for letting me know,” Katsuki grumbled, standing up and walking away. He had to stop projecting his stupid feelings onto Izuku. He made his way to his room.

“No problem, Kacchan,” Izuku responded, almost sounding disappointed. 


iii - rejection

Today was t-minus three days till Izuku hit his heat, so he was still at the agency. Katsuki almost wished he would just go home. 

It wasn’t that he didn’t appreciate the hard work that Izuku did (though he’d be hard pressed to admit it), but the sweet scent that Izuku was letting out, wafting his way every time he passed by his desk, like eating fresh cherries by a creek in the forest… it was making him lose his mind. 

And it was only getting stronger.

In response, Katsuki knew he was releasing his own scent in his desk area, but he could hardly help it. If he didn’t he would just stay drowning in Izuku’s heavenly scent and he might do something insane, like go up to Izuku and kiss him and tell him that if he gave Katsuki a chance he would give it to him hard enough. Too risky.

Katsuki tended to shy away from leaving his scent all over, though. Something about the burnt sugary nature of it tended to make the office betas, omegas, and even some alphas - well. Forget themselves.

It had started with the secretary. “You look nice today, Ground Zero,” she had crooned when he walked in, and he had just bristled and ignored her. Then, a male omega intern, class 2-B at U.A. maybe, had kept finding excuses to come to Katsuki’s desk, like alerting him of changing weather forecasts, or giving him extra printer paper. Annoying, but not so bad.

Then, at lunch, his usual group multiplied by two or three. Instead of just Mina, Kaminari, and Kirishima hanging off of him, regaling him of their latest shenanigans, other heroes and interns were sitting closer than usual in the break room, not hiding too well the way they hung off his every word when he contributed to the conversation.

At one point he made a quip about Mina, something idiotic, and he heard a small laugh a few tables over. He turned, annoyed, expecting it to be another one of his horny coworkers who couldn’t seem to understand the alpha with the burnt caramel scent, but-

Izuku sheepishly waved at him, perhaps smelling the note of irritation Katsuki was releasing. “Hi Kacchan. Is this seat free?” he asked, pointing to the chair right next to him. It wasn’t, Kirishima had been sitting there, and had only left to use the bathroom, but-

“Go ahead.”

The green haired boy smiled at him like the sun, and plopped into the seat with about as much grace as a walrus. His scent was washing over Katsuki like a gentle ocean wave in the rising tide, like the riptide, which would wait till he was unsuspecting before it dragged him out to sea. 

He was in too deep.

Before he realised what he was doing, he was sending out his own pheromones, calming ones like Izuku’s, meant to smooth over the rough edges of the omega’s waves where they were tinged in anxiety.

“Ah- uh, Ground Zero…” he heard a tentative voice say imploringly, and he turned in his seat to notice a young omega girl, maybe 19, standing near him. She had wavy ginger hair, and a glimmer in her eyes. She had to be a new recruit, he had no idea who the girl was.

“Yes? The fuck do you want?” he huffed out, irritated at all the people approaching him because of his scent. Instead of being put off by his tone, the girl just blushed, and held out something to him. Upon further inspection, it was a box of chocolates. 

“I really like you, Ground Zero!” she exclaimed, and Katsuki felt his annoyance just increase. “Please accept these chocolates, and if you were maybe free tonight I would love to go out with you!”

The break room was quiet, and Katsuki hated life. He particularly despised public confessions, he felt like no matter what he did he looked like an asshole.

“Sorry, Kacchan’s actually busy tonight, we have plans,” Izuku’s cold voice cut through the silence.

Katsuki turned to look at him, and saw Izuku’s face drawn and cold, jaw clenched and staring down the girl the way he stared down villains. Izuku’s scarred hand rose to rest on Katski’s thigh, almost possessive.

Katsuki felt his fucking dick twitch.

What the fuck, how was it allowed for Izuku to be so fucking hot here, in the breakroom? 

He knew it wasn’t intentional, and that Izuku had a good reason for speaking for him - but damn. If his alpha didn’t like an omega who could take charge. He’s telling that extra that you're his alpha, Katsuki’s inner alpha preened, and the blonde did his best to shut that delusional voice out.

“In fact, he’s actually going to be busy for a while,” Izuku tacked on, his scent wafting into Katsuki’s nose. It almost smelled - jealous? Katsuki supposed it must be because he was in his preheat, and they were roommates. If Katsuki came home with another omega’s scent on him so close to his heat, he could assume that scent in his safe space probably wouldn’t be welcome. It wasn’t because Izuku didn’t want Katsuki to date her, he just was in preheat, Katsuki reasoned.

The other omega bowed her head, and, weirdly, deposited the chocolates in Izuku’s lap. “My apologies!” she squeaked, before scuttling out of the room. After a moment of silence, conversations resumed, and Izuku smiled at Katsuki like nothing was amiss. He tried one of the chocolates, and then smirked.

“Ah, your admirer has good taste, Kacchan,” Izuku commented, looking almost smug. Katsuki broke out of the trance he was in to snort.

“Thanks, Deku, for that,” he gestured vaguely at the air.

“What?” Izuku’s brows furrowed.

“Shut up, don’t make me repeat it! Just…” he trailed off, and shrugged. “You know how much those confessions fucking piss me off, thanks for making her buzz off,” he huffed out. From the corner of his eye, Katsuki could see Mina facepalm. What? Why? God, she was so fucking weird sometimes. 

Izuku’s eyes narrowed, and he popped another chocolate into his mouth. “Right,” he replied, face becoming stony again. Katsuki just went back to his lunch, though, figuring it must just be another preheat mood swing. It wasn’t like he was wrong and it meant something more to Izuku, right?


iv - cuddling

Before cycles behind, the last two days of preheat or prerut were part of the leave of absence allowed for a breeding cycle. Usually hormones were simply too fluctuational and unreliable in those days, especially for heroes, leading to potential catastrophes waiting to happen.

Meaning, two days before his heat, Katsuki was at the office alone while Izuku was by himself at their apartment. 

And it was driving him crazy.

There he was, sitting at his desk after patrol, trying his fucking hardest to just get paperwork done, and all he could think about was the way Izuku had been cuddled up in mounds of blankets on the couch that morning when he left. He was letting out this heady scent that made Katsuki want to abandon work that day and show Izuku that Katsuki was a far better option than Shindo Yo.

He knew that in the next two days he would have to head over to Kirishima’s. Izuku was frighteningly close to his heat, to the point where his smell was almost always tinged with what had to be arousal. It was making it hard to be in the same room as Izuku, which the omega seemed to be almost taking offense at. He couldn’t help it! It wasn’t like he could say ‘Hey, sorry I keep leaving the room as soon as you walk in, if I don’t I might jump your bones.’ 

Yeah, not happening.

However, sitting at his desk? Maybe even worse. His productivity had gone to shit, and by the time he was leaving the agency, he felt like a shitty hero. He had hardly gotten anything done, and he still didn’t know how to avoid Izuku without making it seem like he was… well, avoiding Izuku.

On his way home, he spent the entire time trying to fortify his mental defenses. It was still too far away to go to Kirishima’s without making Izuku suspect something, but he only had to hold out a few more days. 

When he walked through the door, though, his plans were immediately shattered by the omega running into his arms. 

“Kacchan is home,” Izuku crowed, and Katsuki froze at the feeling of the entire body of Izuku pressing up against him. Izuku’s head was resting in the crook of Katsuki’s neck, so close to the scenting gland Katsuki was almost shivering from the feeling. Beyond that, his chest was pressing against Katsuki’s through the thin shirt the green haired boy was wearing, teasing Katsuki with the warmth, the intimacy, and the divine scent Izuku was giving off. 

The alpha couldn’t move. Hugging… wasn’t something they did. Sure, they shared an apartment and spent lots of time together, and sure, there had been the occasional movie night here or there where one or both of them would nod off and they would find themselves so close when they woke up (Katsuki can specifically remember one time where Izuku’s head had fallen into his lap and he had run his fingers through that soft green hair and felt his heart actually, like, flutter or some shit), but they didn’t hug. This was unmarked territory for Katsuki.

In the back of his mind, Katsuki was screaming to shove him off, cover up his feelings, but with the omega so close and holding him around the middle like this, his alpha was at the forefront of his mind, almost seizing control completely to pick Izuku up and - and -

Fuck. Fuck, not like that. 

With both sides of his mind shrieking at him, Katsuki managed to find the middle ground by (carefully, with a gentle touch) moving his hand up to rest in Izuku’s soft hair.

“Deku,” he intoned, not sure what to say. “What…” Are you doing? Is going on? Do you want? There were so many ways he could end that sentence - “the fuck?”

Izuku pulled away slightly, a flush visible on his cheeks, and looked sheepish. “Ah, sorry. I know Kacchan doesn’t really do touching, I just… with my heat…” Izuku trailed off, looking down, flush gaining territory across his face. Suddenly, it clicked. Ah, Katsuki knew what was going on.

“Oh, like the alpha thing?” he asked. Izuku’s head jerked up, eyes wide.


Katsuki raised an eyebrow. Why the hell was Izuku acting surprised, this is what he wanted, right? “Like, my alpha scent can help calm you down instinctually, right? Isn’t that what this,” he gestured with his free hand to the two of them, “shitshow is?”

It wasn’t unheard of for unmated platonic alphas and omegas to spend time together before breeding cycles simply hanging out, as the opposite pheromones could calm down preheat and prerut anxiety or adrenaline. Surely, Izuku just needed help calming down from something, right?

Confusion, realization, frustration, and then acceptance all flashed on Izuku’s face. Katsuki was astonished at the amount of random emotions Izuku’s preheat was forcing him to feel. He had never known it could be so bad for omegas.

“... Right, thanks Kacchan,” Izuku said, arms feeling a little looser around Katsuki’s middle. Then, they tightened once more. “So you’re okay with cuddling with me?” Big green eyes stared at him.

Katsuki froze. 


As in, Izuku’s body pressed up against him, holding on to him, releasing that beautiful, alluring scent that was crisp and elegant and sensual, hot breaths landing on Katsuki’s skin, on the edge of sleepiness… presumably in his… nest? 


Those green eyes stared at him, echoing hope and desire, and Katsuki was so weak. 

“...Fucking Deku - ugh. Okay, fine,” Katsuki muttered, feeling his cheeks and the tips of his ears burn with an embarrassing flush. God, Izuku was going to be the death of him. 

Slowly, Izuku detached himself from Katsuki, and took a hold of his wrist in order to start leading the alpha. Katsuki nearly choked when he realised Izuku really was taking him to his bedroom, his nest.

“You okay, Kacchan?” Izuku asked, turning around to stare at him with wide eyes.

“I’m fine, nerd,” Katsuki choked out. Izuku only hummed, and kept pulling him until they were inside of his bedroom. Katsuki raised his gaze to see the assortment of blankets and pillows arranged meticulously on Izuku’s queen sized bed. He noticed out of the corner of his eye a flash of black - was that Katsuki’s hoodie?

A flash of warmth travelled through his stomach, making his throat dry. Fuck. It was. Izuku put his hoodie in his nest for his heat. God, Katsuki knew it had to just be a hormonal comfort thing, but that did things to him. 

Izuku stopped pulling him when they got up to the bed, and Katsuki felt the flush on his face strengthen. Thank god the lights were off, or his feelings would become real apparent, real fast.

“How do you-” Katsuki cut himself off. How do you want me? The tension in the room was thick enough to cut with a knife, it felt. Izuku’s silhouette was visible enough in the darkness of his room, and his hand a warmth on Katsuki’s wrist to keep them connected. Slowly, he looked up at Katsuki, the light from the hallway glinting off his irises. 

“Can I-?” he put his hands on Katsuki’s shoulders, moving him only slightly. Embers were coiling in Katsuki’s abdomen, Izuku’s crisp evergreen scent invading his senses, and he sucked in a harsh breath, giving a quick nod. God. 



Izuku’s touch was gentle, and he led Katsuki up to his bed, before pushing him on his back, head on the pillows. The nest was big enough that Katsuki’s toes didn’t touch the edge. It was a big nest, Katsuki noted inwardly, big enough for lots of - of cuddles. Right, that.

His alpha wasn’t even screaming at him, too subdued by Izuku’s scent, his soft touch, the gentle tension floating in between them. You’re so fucking whipped , he told himself. 

“Right,” Izuku was muttering to himself. “Up like that on the pillows, and then of course I, well. I then could do either way and it would work, but which would be better? Well maybe the first option, but then that won’t allow for what I wanted, but second option is too much off the get go and really too much I don’t think I could - I couldn’t do it, of course, I’ll just do the first way like-”

He laid down on his stomach on the bed, face landing on Katsuki’s chest, legs intertwining together, and with his arms splayed out around. His clothes were soft, a thin shirt and thinner sweatpants, and Katsuki wanted nothing more than to flip them over, to push Izuku into the bed, to claim him, to show him what a real alpha is like, to-

“Like this?” Izuku finished his mumbling. 

Katsuki let out a low breath, body tense, and he felt Izuku huff. “Not right,” he muttered, and Katsuki felt his heart clench. Had Izuku changed his mind? God, the scent in here was heavenly, pressed right up against Izuku’s warm body, but did the omega not want him there anymore?

Izuku grabbed one of Katsuki’s arms, and put it around his middle. “Better,” he hummed out, breath coming out hot on Katsuki’s collarbones. The alpha shivered, but took the hint and pulled Izuku close with an arm around his waist. Fucking hell, his shirt was tugging up around his hip, leaving just hot skin, bare to his touch.

The omega in his grip shuddered slightly at the touch, jostling his crotch against Katsuki’s thighs, and the alpha nearly whimpered. God, he could barely control himself now, how was he supposed to continue cuddling with Izuku for longer than a minute without trying to rip his clothes off?

They were already in his nest, and he was releasing such a sweet smell, perfect in the taste of Katsuki and his alpha, his skin was so hot and Izuku was so precious in his arms, pliant, tender, he could just-

No! Fuck. Katsuki took a deep breath through his mouth to avoid breathing in more of Izuku’s heavenly scent. He could do this. He had to do this. Izuku was trusting him as a friend to come into his nest and calm down his hormones. He would not lose to his secondary gender and make the omega uncomfortable. 

“-chan, Kacchan,” Izuku murmured, right next to Katsuki’s ear, and god if that didn’t do things to his dick. Thinking of his grandma, his mom, his math teacher from 7th grade, whatever he had to do in order to stay soft, he responded.

“Yeah, Deku?”

“... Thanks for this,” the omega said, sounding like he was smiling. Fuck, Katsuki wanted to kiss that smile. He wanted to take Izuku out to soft dinner dates in the candlelight and open doors for him and fuck him nice, exactly how he would want it and then cook him breakfast in the morning, something healthy and hearty, not that crap cereal shit Izuku usually ate. He was so fucked. 

And it almost sounded like there was something akin to hope in Izuku’s voice. For a moment, Katsuki could almost believe that Izuku wanted him, wanted the things that he wanted, and led Katsuki into his nest in order to prove it.

But Katsuki knew he was just projecting his own feelings onto the omega. He knew that even if in 99 out of 100 cases an omega bringing an alpha into their nest was a blatant invitation to mate, this was the 1 in 100 platonic case. Izuku would never want him the way Katsuki yearned for his touch, his scent, his love. 

“Whatever, nerd. What are friends for?”

Izuku let out a soft sigh. Ah, he must be relaxed. Katsuki allowed himself to settle deeper in the bed, pulling the omega tightly against him. Anything for Izuku. 



v - scenting

Katsuki’s first thought when he woke up the next morning was that he was starving. 

He hadn’t eaten after he got home, just gone right into Izuku’s nest to cuddle with him, so the last thing he had eaten was lunch the day before. Not that he would take back a night of running his hand through Izuku’s soft hair, hearing the gentle croons of appeasement from the omega, and feeling his muscular but soft body pressed up against Katsuki’s. 

His second thought was that Izuku was awake. 

“Al- Kacchan,” a soft voice spoke, and Katsuki felt a hot coil of embers sink through his skin at the sound of Izuku almost calling him alpha. The omega’s body was still pressed up against his, only now they were on their sides spooning. Katsuki could feel Izuku’s ass pressing right up against his groin, and he couldn’t help but send up a quick prayer of thanks to the gods of self control and not getting morning wood that he wasn’t hard. 

“Zuku?” he rasped out in a tired morning voice. He felt the omega shudder against him, ass doing criminal things against his body, and his grip tightened on Izuku’s waist, holding him in place. Fuck, was that really Isuku’s reaction to just hearing Katsuki call him by his name? 

“I’m hungry,” Izuku mumbled into the morning air. Katsuki let a smile crawl over his lips, it wasn’t like Izuku would be able to see it facing the other way. He took a second to drink in the moment. Izuku, in his arms, letting out the scent of a content omega. His skin warm to Katsuki’s touch, sunlight gently drifting through the window… it was the type of morning he could get used to. 

“Is that your shitty roundabout way of begging me for food, nerd?” he teased, squeezing Izuku’s hip in his hand. Instead of giggling, or shooting back with more banter, though-

Yes please, Kacchan,” the omega whined, back arching into Katsuki’s chest, head lolling to the side to expose his unclaimed neck and scent glands. Fuck. Katsuki bit his lip to avoid sinking his teeth into Izuku’s exposed skin. Was the omega trying to make him pop a boner right here in his nest? What the fuck?

It’s just the preheat making him act different , Katsuki told himself. Don’t take advantage of this don’t take advantage of him he doesn’t mean it like that don’t make him uncomfortable don’t-

“Tch. Fucking leech. Fine, I have to get up anyways for work so I can probably make you something before I go-”


Katsuki froze. The omega’s tone had turned cold. Izuku shifted to turn around in Katsuki’s arms till their faces were only a few centimeters apart. Izuku slung one of his own arms around Katsuki’s waist, pulling himself close and pressing their chests up against each other. His eyes still had a sleepy glaze over them, and his lips were parted slightly in a small yawn. Cute. 

“Don’t go in today,” Izuku said again, and Katsuki felt his brow furrow in confusion. Why was Izuku trying to stop him from going into work? “I…” Izuku seemed to be thinking of the same thing. Why would Kastuki not go in? “It’s so close to my heat… and you… help a lot,” he murmured, turning his eyes to the side to avoid making eye contact. 

The omega’s cheeks turned pink, and Katsuki felt his own cheeks develop a flush. If he didn’t know better, he would think Izuku was trying to - to proposition him or something. 

He should go down in history as the alpha with the most self control in the world, he thought. 

“Deku, you think villains are going to stop pulling shit just because you’re ho - you’re - nesting?!” Katsuki felt his blush deepen. He had almost said horny, and the implications of that would have been just too much for him to handle. 

In his arms still, Izuku turned his gaze back up to face the alpha. “It’s just one day, Kacchan. Please? Of course, I know I am not that important in the grand scheme of things and Ground Zero is such a strong hero and it is rather selfish of me but I just want-” the omega muttered, and at the words not that important Katsuki felt his resolve break.

“Fine, I’ll fucking try,” he cut the omega off. “But I have to get up to make you breakfast, so do you want to let go of me now?”

Izuku looked down at their intertwined bodies, and seemed to realise only then how tightly he had been holding onto the alpha. “Ahaha! Whoops! Sorry, Kacchan,” he smiled up at the alpha, and Katsuki felt his heart do stupid tap dance steps.

“Whatever,” he grumbled, trying his best not to lament the loss of the warmth of Izuku’s touch as the omega pulled away and sat up on his bed. Katsuki forced himself up, and left the room without looking back at the sight of the omega sitting in his nest, knowing it might not be the best to test his self control like that.

As he started pulling out ingredients from their fridge to make them breakfast, Katsuki balanced his phone on his shoulder to call the agency. The line rang twice, before connecting him with that secretary at the front desk. 

“Ground Zero, right? This is the number we have on file for you-”

“Yeah, yeah. Any chance I can get off today?” He asked, not wanting to stick around to chat.

To his surprise, the secretary giggled. As in. Actually laughed at him. Was she making fun of him? How dare she! 

“Of course, Ground Zero, I’m surprised it took you this long. All of next week too, right?” she asked, voice high and amused like they were both in on a joke. 

“What?” he balked. “No, where the fuck did you get that idea from? Just today, and I already have the weekend off, no need to go psycho.” He had no idea what the agency was on, hiring someone so simpleminded as to suggest he get many days off when he only asked for one. After all, he wasn’t even calling in sick, just asking! What was wrong with this woman?

The voice on the other side of the phone sighed, sounding disappointed. “Alright, well. Go ahead and take today, and if for any reason at all you change your mind about next week…”

“I won’t.”

“... We’ll see. Well, enjoy your day off, Ground Zero!” and with that, she hung up on him. He gaped at his phone angrily. Did she really just hang up on him?

“What did your phone do to you?” he heard Izuku laugh at him, the crisp forest scent following the omega into the kitchen. He looked up to see Izuku had changed into a pair of shorts and a zip up jacket. Upon closer inspection, the jacket, which was zipped up only to around the pec area, had no shirt underneath it. Izuku’s pale, milky collarbones sprinkled with freckles were bare to his gaze.

Katsuki felt heat in his groin.

“Fucking stupid ass secretary hung up on me,” he grumbled, hands busying themselves with the food he was preparing. Izuku preened at the scent of cooking food, hovering by the counter with heavy lidded eyes. “... Got the day off, though.”

“That’s great, Kacchan! Thank you for…”

“For making your food and dealin' with your shit, I know,” Katsuki grumbled, not actually upset in the slightest. Izuku was sitting on a stool at their kitchen island, watching him cook with fond eyes. It made Katsuki’s alpha purr. 

We provide so well for omega, his alpha was crooning, and Katsuki wished he knew a way to hit himself that would make his secondary gender shut the fuck up already.

Breakfast was a quiet affair, strangely enough. Izuku seemed to be struggling with something that he wanted to say, and kept cutting himself off before he could go through with it. By the time they were finished, and Katsuki started washing dishes in their sink, Izuku’s bottom lip was bright red from how much he’d been worrying it between his teeth.

“Hey, nerd, dry for me?” Katsuki broke the silence between them, offering an olive branch, almost. He knew that if Izuku didn’t want to talk about, well, whatever it was that he didn’t want to talk about, then it would be a waste of time to try and get it out of him.

Izuku wordlessly started taking the wet dishes from Katsuki and drying them with a clean towel, still looking nervous, almost, and muttering under his breath. Katsuki was sure he heard his own name littered in those mutters, but that wasn’t exactly something rare. 

Finally, as they were finished with the last of the dishes, Izuku broke his silence.

“Is Kacchan still planning on going to Kirishima’s later today?”

His voice was quiet, tentative. Katsuki felt his brow furrowed in confusion, and agitation. All this silence, all this buildup - for that?

“Yeah? What about it, Deku?” He asked, voice incredulous. Izuku bit down on his lip again, hesitant. “Fucking hell, just spit it out!” Katsuki huffed, feeling his irritation spike.

“I’m going to the supermarket, later!” Izuku shouted back, eyes wide.


“And, well. I’m really close to my heat starting, and I’m out of scent blockers!” The omega’s chest was heaving. “And - well. Before you go, maybe you could do another favor for me? Please?”

The ‘ please’ hit Katsuki right in the dick. Sure, he was a strong guy, but seeing his crush in front of him, eyes glistening, chest heaving, releasing a sweet scent that made him want to pick Izuku up and have his way with him, asking please? It did things to him.

“You want me to… go to the store for you? Is that it?”

Something felt off. For some reason, Katsuki knew that wasn’t the right answer, and the tension in the air was increasing. His alpha was sitting back in his brain, not making any input, which made Katsuki even more suspicious. The scent that Izuku was releasing was tinged with something Katsuki couldn’t quite place. What the hell was going on?

“No. I mean - not really. I just, well, smelling like this ,” Izuku gestured to himself, “can make it hard to get what I need unnoticed, and - and I thought before you left you could maybe - help me - you could - cover it?”

The earth seemed to stop spinning. Katsuki felt his hands clench over the towel still in his hands, eyes widening with disbelief. There was no way he could misinterpret what Izuku just asked him to do. Izuku wanted Katsuki to help him cover his preheat scent, and there was only one way that Katsuki knew of doing that. Izuku wanted him to-

 “You want me to do what?”

Izuku clenches his fingers in the hem of his shirt nervously, before looking shyly up at Katsuki. “Well, with my pre-heat there’s more people who… want to… you know , and maybe if you scented me they would back off?”

Alarms were ringing in Katsuki’s head. His mouth felt dry. 

“Shitty nerd, you’ve fought villains who would make these people run crying, and you can’t tell them you don’t want to fuck them?”

“Fighting villians is different from social anxiety, Kacchan! I just want to be able to go to the supermarket without people accosting me!”

Katsuki’s mind was racing. Izuku, sweet, passionate, earnest Izuku with his fucking scent so strong it was making him lose his mind. Yeah, he could kind of see why Izuku was getting hit on so much when he went out, his scent was like fucking god, and Katsuki was a believer.

But no matter how much he made it into him helping Izuku in his head, there was no way to deny that scenting was something for mates. Was this some sort of twisted prank? Flaunt his sensual scent all over the place, drape his body all over Katsuki in their home and fall asleep next to him, be possessive over him at work, and now ask him to scent him, effectively claiming Izuku - all while keeping up that platonic barrier? Was Izuku playing some sort of sick joke on Katsuki? Was he trying to kill him?

“Plus,” Izuku started mumbling, shuffling to squeeze his thighs tighter together while standing up against their kitchen counter (and fuck, what that visual was doing for Katsuki’s horny imagination), “I’ve known Kacchan forever, and my nerves are kinda still going everywhere, and you're so amazing and strong and alpha’s scent would make my nerves calm down and my heat easier like when we cuddled, and if, well, Kacchan wanted to help me - maybe -”

“Shut the fuck up,” Katsuki interrupted, face aflame, the words amazing and strong and alpha echoing around in his head in Izuku’s voice. If he didn’t control himself he might pop a boner right here in their kitchen. “Fine. I’ll do it.”

Izuku looked up at him with huge eyes, bright green and cutting through Katsuki’s defenses like paper.


“Really, idiot. Get over here before I change my fucking mind,” Katsuki grumbled, trying to mask how fucking nervous he was. Oh fucking god, oh fuck - was he really about to scent Izuku?

As in, the buffest, sexiest, most powerful omega in Japan, probably the world. As in, the only omega that Katsuki’s alpha was interested in and had been interested in for years. As in (maybe (read: definitely) the love of his life) his crush , Izuku.

The omega rounded the counter quickly, taking Katsuki’s warning to heart. He sidled up close to Katsuki, chests almost touching, before stopping, hesitant. “Um, how does Kacchan want to..” Izuku trailed off.

Katsuki’s heart was pounding in his chest. He felt dangerously close to losing control to his alpha, which was now fighting for the reins. “It’s your - fucking - scenting, nerd, how do you want to?” He challenged. Usually, when he used this tone of voice, Izuku would respond to the challenge, fight back with that spark in his eye and flare in his attitude that made Katsuki want to chase him and pin him down and - ahem. 

But - this time?

Izuku’s eyes watered, color flickering blue amidst the green, and his full body shuddered. “Want it… however alpha wants me,” he murmured, looking up under long lashes at Katsuki.

This whole week had been a testimony to Katsuki’s absurd levels of self control. The flaunting and need for compliments, the rejecting that other omega in public, informing Katsuki that no other alpha would be there - that, he could take. He could even somehow take the cuddling, holding Izuku’s precious body close to him, sleeping in the same bed, but he was at his wits end, and at the words however alpha wants me-

Kastuki snapped.

Before he knew it, he had Izuku pinned up against the wall, one hand on his waist, the other holding him up over the other boy. He heard a growl lace the air, before realizing it was coming from him. Izuku’s head lolled to the side, a gasp escaping his lips, and the omega’s hands came up to loop around Katsuki’s neck, pulling him closer. 

Sweet omega, my omega , his alpha purred, and Katsuki was barely mentally present as he dove his face down into the junction between Izuku’s neck and shoulder, where his scent glands were. 

Up close: Greenery, crisp forest, fruit so ripe it was bursting, like Izuku was aching for it.

Distantly, Katsuki was aware that his hips were rolling against the omega’s, the fire inside him consuming his inhibitions till all that was left was scent, breed, claim.

“Kac-chan,” Izuku whimpered. The omega’s hips dragged against his, moving too, but Katsuki could barely tell.

Katsuki inhaled deeply, consuming the omega’s scent and stamping his own all over. The hand he had on Izuku’s waist squeezed his hot skin through the thin material of his hoodie, and the omega let out another soft sound.

Scent, breed, claim, mine.

His cock was aching, reaching full hardness just from grinding against Izuku’s thigh, but it wasn’t what he wanted. He shoved his own thigh in between Izuku’s legs and the omega immediately began using it, grinding his omegan dick on Katsuki’s thigh, chasing his own pleasure.

Katsuki nipped lightly at the skin of Izuku’s neck, and the omega let out a throaty moan. More.  The hand he had on Izuku’s waist slipped under his hoodie, not moving anywhere, just tracing the hipbone there, feeling the omega’s hot skin, while Katsuki continued to litter the skin there with kisses, kitten licks, occasionally stopping in a specific place to suck a mark into existence. 

He knew his scent had to be all over the omega by now, but still, he grabbed one of Izuku’s hands and brought his wrist up to his face, the smaller scenting glands there oozing that sweet aroma. The alpha began the same treatment on Izuku’s wrist that he had done on his neck, sniffing and biting and licking. 

The scent around him of the omega was so much stronger than he had ever smelled it, and a distinct note of something was on the edge of it. Sniffing deeper, Katsuki felt his dick twitch when he realized he was smelling the omega’s slick .

Izuku’s slick . Izuku’s sweet smell, his soft skin, his defined muscles, his strong legs. Izuku’s panting breaths whimpers, his broken pleads and begs. 



Katsuki’s alpha was screaming at him to continue, to pick Izuku up and bring him to his nest, to take off his stupid hoodie that showed way too much collarbone and put a claiming bite there, to take Izuku’s shorts and everything off, push inside, show his omega what a real alpha fucked like - 

“Wait!” Katsuki hissed out, hands trembling. He felt his eyes grow wider, and was suddenly very, very aware of himself. Very aware of his hand edging upwards on Izuku’s chest under his clothes, very aware of the wrist he had restrained with his other hand, very aware of the hickeys beginning to bloom on Izuku’s collarbone, of the spit dripping there.

Very aware of Izuku, frozen against the wall, omega cock hard against Katsuki’s thigh between his legs. Very aware of his own cock, hot and heavy in his pants. 

Slowly, he raised his gaze to meet Izuku’s. 

His eyes were blue - the sign of an omega in heat.

The only sounds in the room were their heavy breaths, and Katsuki felt his heart drop in his stomach.

“Katsuki…” Izuku whispered, lids heavy. “ Alpha .”

His heartbeat loud enough that Katsuki could hear it in his head, could feel it in his stomach down to his feet, the alpha forced himself off of Izuku, feeling sick to his stomach. His breaths started coming out stilted, and he removed his hands from the omega’s body, holding them palms open, eyes flickering down to stare at them. What had he just done?

“I - you should be good to go now,” Katsuki said in an  uncharacteristically tense voice. How could he be brash and confident when he’d just made the biggest blunder of his life? Izuku’s eyes fluttered in confusion, his brow furrowing in confusion. 

And Katsuki was a strong alpha, a hero, a proud man. He faced his problems head on, he wasn’t afraid of confrontation. He was loud, he was intimidating, he didn’t give a damn what people thought of him, and he had faced countless villains without falling, he always came out on top.

But this time?

He ran.