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But Now I Got a Bellyache

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Izuku's heart beat hotly in his ears as he felt flush run up his body and into his ears and cheeks. Below him, Recovery Girl leaned in, listening closely to the stethoscope currently pressed against the boy's upper navel. The cool metal burned against his skin oddly enough, making him feel somewhat feverous. The clock hanging crookedly on the wall ticked over several beats, stretching out his wait and being the only noise in the bleak room. His eyes burned into it, too shy to bother making eye comtact or seeig what she was doing. He waited awkwardly for a few moments until the older woman pulled away and motioned for him to lower his shirt.

"Everything sounds fine. Just a little bruising but I imagine that's something you can heal up on by yourself relatively quickly. No kisses today." She sat back and smiled softly, setting aside her stethoscope and clipboard.

Izuku breathed out a huff and nodded curtly, straightening his back. She'd been referring of course, to this afternoon's latest fight. A simple sparring match with Ojirou had ended in Izuku clumsily tripping just at the same time as the blond boy's well-muscled tail slammed down at him. The wind was knocked out of him, which ordinarily would have been brushed off, but the second he stood up he collapsed. He woke up a moment later, complete with a bloody nose and nasty headache. Normally, something like this wasn't that bizarre, given his...interesting track record. But as far as injuries went, he couldn't afford anymore. At least, that's what Aizawa had told him when he commanded Izuku to leave practice early.

"As far as the fainting goes, I think it's probably just you either overworking yourself or not drinking enough water or eating enough food to correlate with your workout." The older woman coolly explained, pushing her glasses up. "How many times have you had a fainting spell or felt nauseous or lightheaded in the last two weeks? I'm thinking a previous head injury hasn't properly healed, or there's an injury you haven't told me about."

"I've been trying to keep better care of myself..." Izuku nervously laughed, trying not to let the embarrassment of what she was suggesting obvious. He shifted, reflecting for a second before shrugging. "But nausea...I don't know...only four or five times I think? I just assumed I was catching a stomach bug."

Recovery Girl hummed to herself momentarily, turning to write something back down on the clipboard.

"Any hot or cold spells recently? Or unusual tenderness around your waist and hips?"

He nodded, hand unconsciously reaching for his side. His knee bounced, nervousness clear. "Yeah, I've had a few moments like that in the past few days."

She nodded again, scribbling a few notes down. "I hate to ask but when was your last heat, Midoriya?"

The green-haired teen flinched in surprise.

Oh yeah. That. 

He was still so unused to the word that he was surprised for a split second. He glanced down, somewhat kicking his dangling legs as he mulled the thought over. It was still such a foreign subject to him, something he didn't think about often or forgot about most of the time. He hadn't ever seen himself as an omega before nearly half a year ago and was still a fledgling when it came to his experiences with any of it. Most of what he knew had come from brief sex-ed lessons at his old school, and the occasional online search from when he was bored and curious. Shaking the ramblings from his head, he exasperated a huff and looked back up to meet her eyes, nervously scratching the back of his neck.

"I think it was just a month ago? I'd been on suppressants so I didn't really feel it outside of occasional nausea or feeling tired." It didn't take much for him to connect the dots, having already pieced together what the nurse was getting at. "You don't think it's something to do with that, do you?"

"Hmm. It might be." She murmured back, not easing his worries much. "It might just be a bug though, like you said. How many heats have you had since your transition from Beta to Omega?"

"Only the two, including that one."

"You shouldn't be going into another for at least a month, a month and a half then, I assume?"


Midoriya looked back down at his feet, frowning slightly. He remembered the day he found out he presented as a beta, just 8 years old to be sorely disappointed for the second time in his life. It would have been impossible to not be a beta, given his circumstances, but that didn't mean it hadn't broken his heart as a kid. All quirkless individuals, at least according to every doctor he'd asked and source he'd looked at, was definitely destined to be a beta. There were no exceptions as far as the little boy knew. Yet after discovering he was quirkless, it had been the one thing he'd been hoping would be different. As a toddler, he'd shown signs of being an alpha after those strange doll tests they used to pass out in Kindergarten, something that had been mandatory for school to track progress of sexual development. 

After his quirkless diagnosis, the young boy had done everything in his power to try changing fate, somehow being the first of his kind to be different. 

As expected, he showed clear signs of beta passage. By the time the official presenting of second sex came around when he was 12, no one was surprised when that was exactly what he got.

Lucky, some kid had bitterly told him after getting his own results. At least you aren't an omega.

All that changed the instant All Might passed on One for All to him.

His mentor had already informed him of the many changes he'd undergo if he went through with it, not wanting to get his hopes up or make him feel like he was scamming him. According to him, if you were quirkless before obtaining it, you would undergo a change and transition either into an Alpha or an Omega. It was the decision All Might and the mentors before him had to make, something he'd have to choose.

Izuku had hesitated. Just for a second. He was excited at first of getting his dream of presenting as an alpha, but the idea of being an omega has him stilling. It was never that he hated omegas, he treated them as he would any other person. It was more the stereotype that had immediately popped into his head. He couldn't really help it, the thought of the scrawny, effeminate Omega father meekly carrying several kids as his much manlier alpha bossed him around. He felt bad for thinking it, but it only lasted a moment. 

And without contemplating it further, Izuku accepted. His desire to be a hero had always outweighed his desire to be a beta or even greater, an alpha, and with that, he never looked back.

"I understand you're quite new to this, right?"

Izuku's head snapped off, caught off gard by his thoughts.

"O-oh, yeah."

"Alright, I'm not surprised then. Let me explain-It's not uncommon for new omegas to have unusual, random heats," Recovery Girl chimed. "It happens more often than you would think actually. Your body isn't quite used to the hormones in your body, so it tries to level it out by forcing them more often in shorter heats or less often in lengthier heats. It can take up to 10 months to fully regulate, but it usually won't. This is only your fifth month, correct?"

Izuku nodded, taking in the knowledge with an edge of disappointment. "Yes, but I didn't get it until 2 weeks after the entrance exam, or the day after receiving my quirk."

She merely nodded, seeming used to the bizarre situation. "Don't worry, it should be okay. I'm going to assume its just signs of an early heat, okay? I'll prescribe you some suppressants- I assume you don't have any on you- and pain and nausea pills just in case it gets nasty. Take one suppressant for now and if your heat doesn't start up in the next 2 days take another. If you wake up and feel too dizzy to walk, I recommend just staying in at home until it passes over. Just call me and I'll write you an excuse."

She stood up and Midoriya jumped to follow her, still feeling sour over the news. She led him over to a tall metal cabinet, undoing the padlock and pulling open the doors. He watched as she shifted through several rows of bottles, before coming across three she needed and grasping them. She locked the door and handed them over to him. He hastily stuffed them in his pockets, backing up so she could lead him back to the door.

"Can I go back to class?"

Recovery Girl scoffed. "Always eager to get right back into trouble, I see. Fine, but take it easy and if it happens again, head to your room and sleep it off. I expect it will hit you anytime in the next two days but I'm not sure. You can resume school until then."

Izuku nodded his thanks and headed out.

The hallway was relatively empty, save for a janitor swiveling a cleaning cart down the hall. His class was still out with All MIght, practicing with their quirks and working on development. Izuku decided to head back to his locker last minute, to drop off the medication before he went out to fight. He needed the suppressant to kick in as soon as possible. Sure, the others obviously could smell the omega in him no matter, just the same as when he could smell a beta or an alpha. The last thing he wanted was someone smelling the heat on him though, especially Kacchan or Kaminari of all people. It shouldn't be embarrassing, but generally, most people didn't like that fact getting out. At least, he didn't.

The scent hadn't been obvious for a while, he thought to himself, making his way to the the locker rooms in the gym. It didn't really kick in until a week after the entrance exam. It seemed to hit him one night, not subtle whatsoever. His mother had rushed into his room, worried someone had sneaked in. She immediately took him to the doctor's office, and with great surprise to her and the doctor, and little surprise to him, Izuku was an omega. With no other explanation, they ruled it as a very, very late development and rare case of a failed test. Izuku had been content enough to leave it at that.

A week later his first heat hit. Just like the scent, it completely overtook him with little warning. One moment he was watching television with his mom, standing up because he felt a little nauseous. The next he found himself vomiting in the bathroom and feeling like his blood was boiling beneath his skin. He locked himself in his room the whole week duration of it. The new feelings he didn't understand and the weird urges overtaking him had been overwhelming at the time, and he'd cried and often worried that it would wreck his chances of being a successful hero. If he was a crybaby before, being in heat just amped that up another 200%.

Then he would remember All Might. The memories of the older man's encouragement, him telling Izuku that he could get through anything if he truly wanted to. And it wasn't as if there weren't omega heroes. Eraserhead and Miruko, just to name a few. In the end, he got through it okay, and by the time his second hit, he was already on medication and had barely felt it. Subtle cramps and more...urges, if anything at all.

The first time Bakugou smelled it on him, the older Alpha had turned in complete disgust, unbelieving of it. He had ended up confronting him later on, shoving him into a wall and demanding Deku tell him why he reeked of omega scum. Midoriya knew he didn't mean that as a genuine insult, or, he hoped so. He was just angry over his assumed explanation of why. That Izuku had hidden the fact he was an omega and had a quirk so well because he must have been scared of Bakugou, or had pretended to be a beta to seem less pathetic. 'You're right to be scared and ashamed, coward,' the blond sneered, tightening his grip on his collar. 'People like you are meant for one thing and you know it.'

He didn't let it get to him. He'd prove him wrong, one day.


Deku rushed up the stairs and out of the commons rooms of the school. He wandered to the locker rooms and spotted his locker number fairly quickly. He only unlocked and opened the locker for a second to toss the bottles of pills randomly onto a pile of training clothes before he slammed the door and relocked it. 

A few minutes later and he was back at the training field. The memories were pushed from his head, and he was back to finishing training. It was tough, but he was getting more and more used to it. It wasn't like it wasn't fun either. Ochaco glanced at him from where she was watching one of the last pairs, turning to smile and wave. 

"Hey, Midoriya!" She beckoned him over and he obliged, rushing up to greet her.

"Hey," he breathed out, stopping abruptly in front of her. Ojirou seemed to catch wind of his voice and turned around, an apologetic look quickly gracing his face. He walked over and stood beside Ochaco, dipping his head slightly.

"Hey, sorry about that. I didn't see you trip right away and by the time I did my reflexes already had acted." His tail wavered slightly as he spoke, curling up to his back. 

"Yeah, are you all right?" Ochaco continued, hands fidgeting nervously. "We were all worried when you fainted like that. We knew you could take more, so it was a little surprising."Ojirou nodded in agreement.

Midoriya just shook his head and sniffled. "No, it's fine. Recovery Girl just said I was coming down with something and needed to take it a little easier. It was nothing you did. " He felt somewhat guilty lying to him when he did trust him, but it still felt new and embarrassing in his eyes. And, it gave him a less private excuse to tell others just in case he did need to take a few days off.

"That's good," Ochaco replied, breathing out in relief.

Ojirou's expression brightened. "I'm glad that's all it is. We can go again after this one if you want? I can go a little easier, though. If you're up for it anyways."

Deku nodded his thanks and smiled warmly. "I'd appreciate it."

Somewhere in the back of his mind it occurred to him he had spaced it and forgotten to take the suppressant in his rush to get back to training, but he merely threw it off. A few hours until he got home couldn't hurt.

The three joined the others in watching the current fight between Tokoyami and Iida unfold. The blasts from Iida's engine blinded the other's Dark Shadow several times, but he managed to push through it. The giant monster ripped Iida off the stage, catching him by surprise and sweeping him several feet away. Iida regained himself and stood to shake hands with the other male, and they walked offstage. Iida glanced in Izuku's direction, sending him a soft smile before he stood off to the side.

Another fight between Kirishima and Aishido was pulled on before he and Ojirou were called up.

As Izuku walked onstage he couldn't help but pout slightly, already imagining how finished he'd be feeling in the next few days.


 By the time the school day dulled around to the end, Midoriya felt sore and tired. The tenderness he'd felt earlier hit him and he felt more tired than a day like this would have usually rendered him. He made it back to the commons area in the school alongside Ochaco and Iida. The omega girl and alpha boy beside him were eagerly discussing the battles from earlier. Normally, Deku would have joined in a heartbeat, but the weight of the day had him dragging his feet and almost yawning.

They settled in on the couches in the lounge, with a few others following and joining them. The conversation drifted to several different subjects, the tired boy only ever adding his thoughts when asked and in a few words at most. Right now, they were all heavily talking about the signature moves everyone had in development and the new costumes people were contemplating or already having made.

Izuku smiled to himself. He loved this part of UA the most. The friends he'd made here which had accepted him without any hesitation and were so open and friendly. It felt so close to being a family even. He wished moments like this would never end. He could relive this for years and never tire of the warmth of it all.


When Izuku got home, he was exhausted. His mom offered him dinner, but he could only manage a small bowl before the sleep tugging at his joints forced him to resign for the night. He wished her a quick goodnight, before heading up to his room. His door closed quietly behind him, and he slumped against it. The teen released the yawn he had been suppressing and slowly dragged his feet over to the small dresser he kept his clothes in. Izuku grabbed the nearest pair of shorts and t-shirt and got dressed in the dark sluggishly, haphazardly tossing his clothing into the growing heap in the corner of his room. 

He fumbled around in the dark for several agonizing moments. Eventually, his hand came across the bottle he had shoved into his pocket earlier at school. He took two and swallowed them dry, before turning back to his bed.

Within seconds he collapsed under the covers, and tugged the blanket around his form, never bothering once to pull it out.

His eyes lowered and his breathing slowed down into a quiet rumble. Before he knew it, he was dead asleep.


Icy hands traced down the curve of his spine, sending a shudder throughout his warm body. The same hands continued to feel around the base of his back, occasionally lightly scraping at him with his dull nails. Little shivers occasionally racked him at the light touches, making him shift uncomfortably. He moved some more, and the little touches grew firmer. Izuku leaned into the touch, earning a gentle squeeze at his hips. He let out the smallest of whimpers and the hands dipped lower until they were tugging at his waistband. The boy shook his head and groaned, hips twitching slightly. It wasn't going fast enough.

Suddenly, the same hands disappeared, getting the message. One grasped his hair by the roots, pulling him harshly. Izuku let out a cry of surprise, trying to pull back. The other hand gripped his jaw, tilting his face up.

Before he could protest again, lips were crashing down on his. All control seemed to abandon him at the moment, and he hated the way he loved the feel of it. His body leaned further into the kiss as if on instinct, and in response, the other person nipped lightly at his bottom lip. His mouth opened in a sharp gasp, and they took the opportunity to pull him into another, deeper kiss. 

Teeth attacked his mouth until blood was filling his mouth and he could do nothing but whimper at the bites. His chest was flush against theirs, hand still clasped in his hair. The other had worked it's way slowly down from his jaw. It came to rest at the front of his pants, palming lightly and making Izuku groan and push back into it. Whenever he leaned in too close, the hand in his hair would pull him back again, giving the person better access. They moved from biting to licking around the teen's mouth, exploring and playing with spots he gave more response to.

Finally, the person pulled back from the kiss, gasping at the same time as Izuku. Their hand stayed rooted in his hair, easing but still holding him. His eyes cracked open, leaving him to gaze up into their red eyes.

"You belong to me."

Izuku didn't know how long he had been asleep, but when he awoke it was pitch black all around him. He gasped for air, sweat coming off of him at contact with the air. His body felt disgustingly hot, and he felt like he was drowning in the blanket that dwarfed and muffled him. He clawed around blindly, grasping until he managed a hold on the blankets side. He ripped it away and rolled over, his whole body shaking and hot to the touch. His shirt was soaked to his chest, and he could already feel the sticky mess in his shorts.

His body immediately shivered at the coolness, bringing attention to the wetness of his groin. He groaned, not being able to help the small thrust his hips made on their own accord.

Embarrassment heated his face immediately, despite his being the only one there. He felt sick. 

Izuku tried to stand, but the second he did his legs gave out, making him stumble blindly forward. Panic clashed with the lust in his head, his heart beating even faster. He needed to find those suppressants immediately. 

He gave his legs a second to regain themselves before he began to ease along the wall, trying not to trip on the laundry tossed on his floor. When he found the light switch, he flicked it on and quickly turned back to glance around the room. 

His room was a mess. 

The sheets and blankets were tangled and thrown over the side of the beds, his tossing and turning from the wet dream obvious. He could see the soaked sheets, and his face heated even further in disgust. His clothes remained tossed all over the side of the room. 

Midoriya rushed across the room, sifting through the sheets and blankets as he reached around for the bottle. All he needed was to take two and this would be all better in an hour or two, give or take. He could do this, he had to before the heat got worse. He glanced under his bed, relief overwashing him as he caught sight of it. He hastily reached out and grabbed at it, pulling back and sitting on his haunches. He pulled at the cap but immediately froze at the action.

He stared in disbelief. Disappointment and dread consumed him at the sight. 


The damned ibuprofen rested in his palm. He'd grabbed the wrong one. It explained why he woke up to such an intense heat, probably grabbing a different one in his tired state. He must have left the other one at school in the locker rooms.

The teen cursed himself and struggled back up to his feet, regret filling him. He looked around again, anxiousness rejuvenating itself. He ignored the pressing hardness in his pants and forced himself to look around the room wildly. He did it for several seconds, grunting when he saw nothing. He pulled apart his bed and began pulling out his drawers violently, a wild look on his face as his breathing only quickened. He looked for several minutes until it got to be too much and his legs gave out again. Izuku meekly groaned out, arousal intensifying in every passing second. 

Part of him cried out to touch himself, ease the pent-up energy and frustration. He gave in for the moment, pressing his hand against his length, breathing out hard. 

He might have continued from there, but the panic caught up to him through the haze. Midoriya grit his teeth and shook his head, grabbing his thigh and sinking his nails in. After a moment, the arousal died down for the most part. He rushed to get back up, knowing it would be back in just a moment.

The teen gave up on looking to see if he might have brought it, and scrambled to change his clothes. If Midoriya couldn't find it now, he'd just go run and get some from the medicine cabinet, no big deal.

He threw on his loosest pair of sweats and an oversized hoodie, not bothering to change the sweat-stained shirt.

A minute later, he was rushing down the block's hallway. He was hoping- no, praying, he wouldn't run into a teacher or another student. Especially an alpha. He couldn't do that right now. Alphas had a better sense of smell, and the second he smelled one or they smelled him it would too late. He was embarrassed enough as it was and he was the only who knew. No way in hell would he let someone else see him like this. Never.

He pulled his hood over his head and tightened its strings. His pace grew into a run.

He had almost reached the exit when he unexpectedly hit another body as he rounded the corner. He immediately jumped back. The scent of alpha hit his nostrils within a second.


Izuku softly hissed to himself as he back further away. 

Kirishima stared at him in surprise and confusion, red eyes glistening softly under the fluorescent light.

"Y-yeah?" He attempted to reply. Midoriya nearly punched himself at how weak and broken his voice came out. He might as well write guilt across his forehead with how obvious his voice made it sound.

"Where were you, dude? We were all talking about sneaking out to the pool when we realized you disappeared."

"Oh. Oh! I uh.." He trailed off, eyes suddenly trailing down Kirishima's body. He was in his swimming trunks alone, a towel draped over his shoulder. He stayed on him for a second, before he shook his head at his own staring. Kirishima's brow lowered in further confusion. He stepped forward, making Izuku leap back again as if he had the plague.

"Is something wrong? Are you okay?"

Izuku felt immediate guilt at the worry evident in the redhead's voice. He wished he could do something to ease it, but the scent of alpha screamed at him and he could feel his own pants tightening at just the fantasies swarming his head. Every atom of him was demanding he rush over, but Izuku held back.

'Yeah, yeah! Uh...I'm sick. I came down with a fever. And...I'm looking for the nurse's."

Kirishima stayed quiet for several seconds. Deku almost broke, his paranoia over being caught intensifying. He must know, he had to with all that staring. 

"Oh, jeez. That really sucks..." Kirishima frowned, taking in the flushed appearance of the green-haired boy in front of him, sweat clearly rolling down his face and shivering all the while. He attempted to step closer again, and in turn the other back away even further. "Do you need help or something?"

"No! I mean, no. I don't." Before Kirishima could ask he was interrupted again. "I don't want you to catch it. I'd feel horrible if I got you sick."

"Are you sure?"

"Yeah, I'll be fine. I promise." He threw a shaky thumbs-up and attempted to smile and not look as nervous. He probably still looked sketchy, but after another moment of silence Kirishima nodded and smiled back. His shark-like teeth glistened and he threw back a thumbs-up.

"Alright. Well if you need something or end up feeling better, you know where I- err, we are."

Deku nodded with another forced smile, waving.

"See you, Midoriya."

The redhead turned around and began walking away, Izuku staring after him until he eventually vanished past the exit doors. He immediately released the breath he hadn't known he'd been holding, and backed himself up into the wall. He half-collapsed against it. shakily breathing. He let a minute, and then another pass before he straightened himself up again. He found himself grabbing his thigh again, forcing the thoughts he'd conjured up away again. Kirishima should be gone for sure, but he still cautioned himself into running at a much slower pace. At least he'd be able to smell if someone was coming his way again. As he exited the building, he tugged his hoodie tighter around his heated body.

It ended up taking him several minutes longer to reach the building holding the nurse's office than it normally would have. He forced himself to go the long way around, not wanting to chance the shorter route. It crossed directly in front of the pool where Kirishima and likely at least half the class was, and he wasn't going to chance another surprise encounter. The second he entered the building he pushed himself into a full-on sprint, doubting he'd run into anyone now that he was free of his classmates' territory. All the teachers should have left, save for the nurse who typically stayed after hours. 

Izuku made it up to the third floor using his full-cowl relatively quickly, skidding to a stop at the door. He gazed up at it hopefully, breath catching.

He really hated his luck today.

The lights were off and when Izuku twisted the knob, I stayed still. Agitation set in his muscles. He found his fists clenching and his brows furrowing within a second. Tears threatened to spill and he made no attempt to hold them back. His fist banged against it as he slumped forward. His teeth grit, being the only barrier to hold back the choked-up sob escaping his throat. He felt disappointed, but mostly in his self. Why he never bothered to check the time the moment he got the idea to try finding Recovery Girl eluded him. His nails dug into his palm irritably.

He had no idea what to do.

Waiting it out was next to impossible. The idea of locking himself in for possibly a week repelled him. People would know what was up by the time the third day hit. It was a no-brainer.

Part of the teen considered heading back and begging one of his other fellow omega classmates for help, but he rejected the idea as quickly as he thought it up. He didn't want to go around knocking on their doors in his messed-up state and chance disturbing them, or a non-omega in that block who might overhear. He couldn't go to the pool area either. Guarantee everyone would smell the lewd scent he was giving off like a dog, and guarantee they'd want to know why he was there even if they didn't. 

Just the thought of Bacchan sneering at him in disgust made him sob even harder. 

Izuku sat with his knees pulled up to his chest as he cried. He should call his mom. She'd know what to do. She always did, she always was there. How disappointed she'd be, though. First chance he had to be on his own and prove himself to her, make her even prouder, and he had messed up. She'd ask- no, demand he come home the second he was back in her arms. No way would Inko let something like this happen ever again. She loved her son way too much, which at the moment was more of a reason to cry about it than anything. He sat there for twenty minutes, quietly tearing up to himself until eventually, his eyes dried on their own and he couldn't cry anymore.

No, Deku finally decided. He pulled himself to his feet and swiped a hand across his wet cheeks. He was an adult now. Close to being one anyway. He had to do this on his own. The sooner he learned how to grow up and past this, the better. It might not be the first time it would happen, and he couldn't cry to his mother every time something bad happened. He needed to get stronger, for her and himself. 

Izuku heaved out a heavy breath of air, still shaky from crying. 

He went with his final plan, the only other thing he could think of: going off and buying them himself. 

It was late, but he knew a 24-hour convenience store about 30 minutes away from the school, 15 minutes if he ran. 

Izuku sniffled, only thinking it over another moment. He could do this. He had to.

His full cowl activated, and Izuku found himself dashing wildly out of the school, determination in his eyes.

Somewhere, in the back of his head, he knew it was going to be a long night.