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It happened in math class, of all places.
This furthered Aoki’s conviction that math should die, because not only did derivatives hurt him emotionally, time and again, by proving to him what a dumbass he was–not only did seeing inverse trigonometric functions on his test paper actually cause him to throw up in class last year (granted, he did have food poisoning, but that was beside the point), among other grievances–
No. As it turned out, the limit did not exist when it came to the nefarious capabilities of mathematics.
In hindsight, maybe he should have known.
Maybe he should have gotten the hint when he started being inexplicably drawn to Ida’s laundry hamper.
At that point, Aoki had stolen two hoodies and one volleyball jersey, and he didn’t even come close to connecting the dots.
It was probably because Ida had witnessed this theft (committed in broad daylight) and did nothing, even smiling at Aoki fondly and treating it as the most natural thing in the world when Aoki sniffed around his stuff.
So Aoki didn't think much of it, either–but now that he thought about it, stealing clothes was just plain psycho behavior for anyone, but especially for a beta.
A week ago, Aoki spontaneously dropped all of his shyness with physical touch. When they were alone, he clung to Ida, inhaling his scent. Ida smelled nice, like shampoo and soap, but Aoki’s nose was not satisfied, and he greyhounded his boyfriend’s neck in search of that missing smell.
Again, Ida didn't comment on this new development. He simply returned Aoki’s affection, kissing him softly on the cheek or wrapping his arms around him. Or else he would reciprocate and rub his nose in Aoki’s neck, remarking about how good he smelled.
So in a way, it was kind of Ida's fault. He was clearly in cahoots with math to overturn Aoki’s peaceful beta existence.
Aoki was busy not paying attention in class when he suddenly smelled something delectable.
Now, since he had officially joined the baking club, he was no stranger to wonderful smells–chocolate chip cookies in the oven, homemade fruit preserves, Hashimoto’s strawberry shampoo (which, okay, even if he didn’t like her romantically anymore, still smelled pretty damn good).
This scent was…different. And completely foreign.
But also…kind of familiar?
Aoki took a deep breath.
The smell was not only delicious, it also had weird soothing abilities. Because while normally, looking at a blackboard full of equations made him want to yank his eyelashes out individually, something in the scent made him feel relaxed.
Tranquil.
It reminded him of last week, when he and Ida had dozed off in bed together after pulling an all-nighter. Aoki, sprawled next to his boyfriend, lay half-awake, and the air felt heavy, almost thick enough for him to snuggle into.
Now, Aoki sighed dreamily. Numbers are nice. Math is good. I love math.
And then, Aoki was suddenly struck by a bolt of lightning.
Well, that was what it felt like, anyway. Aoki’s body was simultaneously tense and shaking, and that, coupled with whatever expression he had on right now, probably made him look like a glitching, badly-rendered video game character.
He slumped onto his desk with a painful thud, and there, he proceeded to hyperventilate.
Not Aoki-hyperventilate, but actually hyperventilate. His mouth was wide open but it couldn’t take in enough air, his ribs were crushing his lungs, and he was making very graceful dying goat noises for all his classmates to hear.
He tried to breathe in through his nose and found that he could, but that everything smelled…really intense. And overwhelming, like a million tiny people were cooking or baking or gardening around his nose.
“Aoki.”
A firm hand grasped his shoulder, and Aoki was suddenly able to breathe.
A sudden rush of scent that completely drowned out everything else, like decadent, dark chocolate and bonfire smoke.
Alpha.
Aoki might have been able to breathe, but he was definitely not done panicking, because what the hell was that voice in his head just now?
Before he could dwell on it, Ida was suddenly helping him stand–large, firm hands holding his and pulling him up.
Through the flashes of color and snatches of other scents, he managed to register the concerned murmurs of their classmates as they stumbled to the door.
But all he could focus on was the warmth of Ida’s arm around his waist. The rumble of Ida’s serious voice (which Aoki could feel more than hear with their bodies pressed so close together) as he spoke to their teacher.
And above everything else, his scent.
Ida smelled incredible, and Aoki was all but drooling as he was whisked out of the room in Ida’s arms as if they were dancing Cinderella’s waltz.
“Are you okay?”
Aoki blinked rapidly until he could finally see Ida’s face, concerned and sweet. Aoki realized that he was actually drooling.
He tried to raise a hand to wipe it off, but that would require pulling away from Ida and he really didn’t want to do that.
Aoki nuzzled closer to Ida, face breaking into an undoubtedly goofy smile as Ida ruffled his hair.
“You’re a bit warm.”
Aoki leaned into Ida’s touch and his eyes slipped shut when he heard Ida chuckle.
“You’re going to be okay,” Ida promised.
If Ida said everything was going to be okay, then it was definitely true. Aoki purred, content.
And then his eyes flew open because what was that sound he just made? Why did he feel so warm? Why did Ida smell so good?
Ida steadied Aoki as he began to sway in his arms, dizzy and overwhelmed. “Hey, calm down…”
They sat in a deserted nook under a staircase. Ida crooned over Aoki, running his fingers through his hair, massaging his shoulders.
Aoki was feeling calmer and a bit more aware of his surroundings. It helped to have Ida there to focus on, like a port in a storm.
Ida squeezed his hand. “Can I scent you?”
Aoki nodded. Alphas and omegas sometimes scented their beta partners, friends, or family members. It was more of a symbolic act than anything, meant only to display affection since betas didn't have scent glands. He always liked it when Ida scented him, though.
Ida rubbed his wrist on a special spot near Aoki’s neck. Aoki keened.
(Seriously, what was up with these weird sounds?)
“Your scent glands,” Ida said, sounding vaguely awed.
Aoki frowned. “I have scent glands?”
“Yeah. They’re not too obvious yet, but I can feel them. In a few days, we’ll see them, too.”
“You know–” Aoki’s throat felt like a rusty drainpipe, but he forced himself to keep talking. "You know what’s happening, don’t you?”
“Yeah, I think so.” Ida stood and gently urged him to continue walking, hand rubbing the small of his back as they made their way to the school clinic. “Your parents had the puberty talk with you, right?”
“Only regular sex ed stuff.” Aoki shrugged weakly. “Every single person in my family is a beta. I think I have, like, a second cousin who was an omega? I’m not entirely sure.”
Ida nodded slowly. “I have a lot of alphas and omegas in my family. People usually present when they’re thirteen or fourteen.”
Aoki sputtered. “Why the hell am I presenting this late?”
“It’s not unheard of,” he said. “My mom is an omega, and she presented when she was sixteen. Some people even present in their early twenties, although that’s definitely rare.”
“Idaaaaa.” And suddenly, Aoki was panicking again. “Do I have to give birth out of my butt?”
Ida stared at him.
And then he burst out laughing, because Aoki’s mate was apparently an inconsiderate jerk and he was doomed to spend the rest of his life with him.
Wait.
His mate?
My mate, some weird voice in his head agreed and Aoki started screeching, because apparently presenting as an omega gives you schizophrenia.
Betas don’t have mates! Betas had boyfriends, girlfriends, husbands, wives.
But…Aoki, quite evidently, was not a beta.
“Aoki!” Ida gripped his shoulders, and Aoki blinked up at him.
A wave of that soothing scent suddenly rushed between them, comforting and strong. Aoki relaxed again, despite himself.
“Ida,” he said petulantly.
Ida smiled. “No, you won’t give birth out of your butt.”
Aoki paled. “Will I give birth out of my dick?”
“No.”
“Is–Is it like those Alien movies? Is the baby going to explode out of my stomach?” Aoki clutched his nonexistent baby bump, fearing for his life.
“No. Aoki, don’t worry about this now. We haven’t even had sex yet.”
Ida brushed his hair from his eyes and gazed at him tenderly. “Look,” he said, “I know this is scary. But you’ll get through it, okay? I’ll be with you the whole time.”
Aoki nodded. It was incredibly hard not to melt like taffy in Ida’s hands.
“You’re my boyfriend, Aoki,” Ida continued. “Nothing is going to change that. You were mine when you were a beta, and you will still be mine even if you’re an omega or an alpha or whatever else.”
Mine.
Aoki shuddered. Sometimes, Ida would say things like that–mine and claim and bond–even when they started dating. The usual alpha-omega jargon that Aoki had been familiar with, but only from a distance.
Aoki had found it a bit weird at first, but he eventually grew to love it. They were words that rang with certainty, just like Ida himself, who put a world of thought into everything he said and did.
Now, the word mine had a physical effect on him.
The voice in his head purred in response. Yours, he thought as he stared into Ida’s eyes.
“Yours,” Aoki echoed. Ida’s eyes widened, and then he smiled.
“I’m yours, too,” Ida said.
“M-Mine?” Aoki blushed scarlet. “Really?”
“Of course."
Mine, the little voice in his head proclaimed, ecstatic. Mine, mine, mine. My alpha.
Aoki scrunched up his nose.
“Hey, Ida? Who the hell is living in my head?”
“That’s you,” Ida said, amused. “Your, ah, primal thoughts. I’m sure you’ve had them even as a beta, though likely not as strong. Alphas and omegas are more aware of their instincts. You’ll learn to tune that out."
“What is yours saying right now?”
“Protect,” Ida said automatically. “Need to keep my mate safe.”
Aoki flushed. “O-Oh.”
Alpha, the voice in his head gushed. Alpha is so strong, need his big kno–
Aoki squawked. Ida shot him a sidelong glance.
“What–?”
“Nothing!” Aoki yelped, face burning.
Ida hummed. “How are you feeling now?”
“A bit woozy. And, um. Warmer than before.”
“You’ll be having your heat in a few hours,” Ida said quietly. He kissed Aoki’s temple, anticipating another freakout that–fortunately–did not come. (Aoki was too busy arguing with his inner omega to freak out.) “I’ll help you through it.”
Aoki’s head shot up. “W-Wait, will we–?”
“No, Aoki. Not yet.” Ida hugged him close, and Aoki purred again. “When omegas are in heat, their alpha’s scent helps calm them down and makes the experience more bearable. Usually they build a nest, but we’ll need to improvise since we didn’t have time to prepare.”
“But don’t you…” Aoki bit his lip.
A lump was forming in his throat. Alpha doesn’t want me. He won’t give me his knot.
And this was ridiculous, because Aoki knew that it couldn’t be further from the truth. But he couldn’t help but voice out his fears anyway.
“Don’t you want me?”
Ida’s eyes softened. “Of course I do,” he murmured. Aoki shivered as Ida nosed his would-be scent gland. “You’re my mate, after all. But this is all happening so fast. I might hurt you if we’re not careful.”
“Can you…Will you be able to control yourself?”
“It will be hard,” Ida admitted. “But–”
“I bet it will be hard,” Aoki blurted out, because apparently being in heat had destroyed his already broken filter even more. He slammed a palm over his mouth in mortification a nanosecond later. His omega side would definitely be whacking him for being undesirable if it had arms to whack him with. “Thorry,” came the muffled mumble under his own palm.
But Ida, sweet Ida, never judged him for being an immature moron. “It’s true,” he admitted. “Since you’re my mate, being around you while you’re in heat will be arousing for me.”
Aoki shrieked in sheer humiliation, face turning red and wanting to roll into the nearest hole to hide. Meanwhile, his omega was preening, delighted beyond belief. Alpha wants me. Alpha wants to kiss me. Alpha wants to fu–
Suddenly, Aoki realized that while his inner omega didn’t have arms to whack him with, Aoki sure did. “Shut up,” he growled, about to hit himself repeatedly in the head until his primal thoughts were beaten out of existence.
But before he could, Ida grabbed his wrist. “Don’t hurt yourself," his mate scolded him gently.
Aoki melted, and for once, he was in sync with his omega. Alpha is so kind. Alpha wants to protect me.
“Don’t worry, Aoki.” Ida kissed his hand in an extremely princely gesture, which made Aoki want to transcend his corporeal form. “Just because you’ll be in heat doesn’t mean we need to do anything. It’s not like those romance mangas you read."
Aoki wanted to interject that he did not read romance mangas, thank you very much, don’t believe anything Akkun says, that guy is a filthy liar, but Ida continued to speak.
“Alphas don’t go feral when an omega is in heat. People may present as alphas or omegas, but we’re human beings first. We can all control our instincts.”
Alpha will keep me safe.
Aoki pulled Ida into another hug. “Okay,” he said softly. “Let’s go, alpha.”
—
Aoki’s parents were justifiably alarmed at first.
The silver lining was that at least they'd gotten to know Ida for over a year as Aoki’s boyfriend.
Seeing as Aoki was eighteen and adamantly did not want his parents to see him in heat, they agreed to take him to an omega center to help him prepare. It was also necessary because Aoki’s family was full of betas, and so they didn’t have a proper heat or rut room in their house.
Before Aoki could get checked in, a doctor had to check his vitals.
“Heats can take a toll on an omega’s body,” Ida explained to Aoki’s parents. They were in the waiting room of the doctor's office. “That’s why it’s important for Aoki to be in good health, so the recovery time won’t be too long.”
Aoki’s dad nodded thoughtfully. He was holding a pamphlet about suppressants, and Aoki’s mother was busy fussing over her son.
“I still can’t believe our son is an omega now,” Aoki’s mom said, ruffling his hair. “There’s a lot we have to learn. Good thing we have Ida-kun to guide us, huh?"
“Ack! Stop it, Mom,” Aoki said, trying to dodge her brash attempts at affection.
“Do your parents know?” Aoki’s mom asked Ida, completely ignoring her son.
Ida nodded. “I called my dad. He said he’d tell Mom.”
“How did he take it?”
“It’s not too unusual for them,” Ida said. “My dad is a beta, but he became an expert on omegas ever since my mom presented. They were high school sweethearts.”
Aoki’s dad raised his eyebrows. “Your father is a beta?”
“That’s right.”
Aoki’s mom considered him. “I’m sure you must have been happy when Souta here presented as an omega.”
Ida tilted his head. “I’m just happy to be here for Aoki no matter what,” he said softly. Aoki smiled at him, and that strengthened Ida’s already strong resolve.
“I’ll be with him the whole time,” Ida promised. Aoki’s parents exchanged a glance.
“Ida-kun,” Aoki’s father said, “you know that we trust you but…we can’t help but worry…”
“I’ve heard stories of alphas when omegas are in heat,” Aoki’s mother cut in. She looked at Ida sternly. “Can you promise that my son will be safe with you?”
Before Ida could respond, Aoki, already weakened and flushed from the first stages of heat, sprang to his feet.
“Ida would never hurt me,” he declared, looking dead serious for once. His eyes were blazing and his hand shot out to grab Ida’s, gripping tight. “He’s never been anything but kind and respectful for as long as I’ve known him. And my omega side claims him as my mate.”
Yours, Ida’s alpha said happily. I’m your mate. Nothing will ever hurt you as long as I’m around.
And that was the end of that. Aoki’s parents were stunned by Aoki’s newfound conviction. They glanced between the two, at their intertwined fingers, and then zeroed in on Ida, who did nothing to hide his proud smile.
“Well.” Aoki’s mother turned away, but not before Ida noticed her misty eyes. “If our Souta trusts you…then, please take care of him for us, Ida-kun.”
Ida stood and squeezed his mate’s hand. Aoki was looking at him with a matching expression on his face, proud to have Ida as his alpha.
“I’ll protect him with my life,” Ida said, before bowing deeply.
—
Omega smells so good…
Ida ignored his own thoughts, focusing on scenting Aoki’s fluffy blankets and pillows.
He spread the freshly-scented blankets and pillows on the bed, then scooped up his half-asleep mate from the couch and laid him on the blankets.
“Kousuke…” Aoki purred, snuggling into the sheets. Ida’s hands froze. Aoki didn’t seem to notice, sighing happily as he enjoyed his first nest.
So beautiful…and he called me ‘Kousuke,’ too…my omega…
Ida forced himself to snap out of it. He had a nest to build, after all.
He took a small pile of clothes and laid them on the nest like croutons on a salad. Hashimoto’s scarf, sweater, and leggings. Aida’s handkerchief and two pairs of track pants in questionable states of cleanliness (which Aoki had stared at disdainfully, but still grudgingly accepted into his nest). Clothes from Aoki’s family.
Ida never really had any experience with making nests, but he knew how they worked, in theory. Aoki lay in bed, watching him through half-lidded eyes as he worked.
For an omega’s heat, using scents from the omega’s platonic relationships provided a great deal of comfort in the early, non-sexual stages. (Ida was pretty sure that Aida’s clothes were a massive turn-off for Aoki.)
But once the heat progresses, the other scents would gradually fade, overpowered by the scent of the omega in the room (or, if the heat was spent with a mate, the mingled scents of the omega and their mate).
“This is nice,” Aoki mumbled, nuzzling Hashimoto’s sweater. Ida tried not to bristle at this. The primal, possessive part of him was not happy about Aoki enjoying any scent but his own.
But tonight wasn’t about Ida–it was about easing his beloved mate into a comfortable heat. So once again, Ida ignored these thoughts and reached for the clothes in his bag.
The uniform Ida wore to school that day, along with his scarf, coat, gloves, spare volleyball jersey–any old thing neatly folded in Ida’s locker, basically, were thoroughly scented and handed to Aoki.
His mate accepted each item of clothing with a pleased smile.
Ida’s heart constricted.
His mate.
Ever since he finally understood his feelings for Aoki, Ida had instantly thought of him as his mate. His alpha side had wholeheartedly embraced the beta, too–cooing whenever Aoki was affectionate or adorable and screaming at Ida to protect and comfort him whenever he wasn’t being his usual sunny self.
On top of that, Aoki always smelled good. Like peaches on a warm summer evening. It was his scent as a beta, and Ida was pleased to discover that he still smelled the same as an omega.
Nothing had changed, really–other than a new world of adorable reactions from Aoki being in tune with his primal, omega thoughts.
But everything was still the same. The man on the bed was Aoki Souta, whom Ida had fallen in love with when he was a beta, and will continue to fall deeper into love with as an omega.
“It’s…it’s hot.” Aoki whimpered as heat began to roll through his body in waves. His face was red, eyes glassy, chest rising with every shallow breath. “Kousuke…”
Ida helped him out of his shirt and pants, leaving him only in his boxers.
Aoki stared at him pleadingly. “You, too?”
“Of course.” Ida removed his shirt, trying not to blush as Aoki stared at him openly.
He knew that heat lowered inhibitions, but Ida wasn’t used to Aoki being so…bold.
And especially not with a hint of lust in his eyes.
Omega wants me, his alpha growled. Must mount.
Aoki lay on the mattress, looking effortlessly enticing. “Come here, alpha,” he whispered.
Ida pointedly ignored his inner alpha’s ravings. Instead, he took a deep breath and slipped into the nest next to his mate. He scented him, rubbing his wrists between the crook of Aoki’s neck and shoulders. “I’m here, Souta,” he said softly.
Aoki whined and reached for his mate, only relaxing when Ida wrapped his arms around him.
“How are you feeling?”
“I feel like I’m running a fever. Is it always supposed to be like this?”
Ida hummed. “The next ones are a lot more intense, actually.”
Aoki groaned. “Just what I needed to hear.”
“First-time heats are often mild compared to your next heat.”
“You can stop talking now.”
Ida laughed. He tangled their legs, effectively spooning his boyfriend.
Aoki sighed. “It actially feels nice, though,” he admitted. “Like there’s…a really bad storm outside, but I’m cozy at home.”
Ida kissed his temple, snuggling deeper into their embrace to nuzzle his scent gland. “You’re so eloquent,” he praised him.
Aoki snorted. “Delirious is probably a better term. Also, why am I still forming coherent sentences? I read that omegas get disoriented in heat.”
“Like I said, the first heat is usually more mild. Its purpose is to get your body acclimated for future heats.”
“So, I won’t be getting horny, then?”
Ida hummed. “Oh, we’ll both be getting horny,” he confirmed. “But we’re not going to do anything about it.”
Aoki turned his head to squint at him. “Why not?!”
“Because I love you.”
“That’s a terrible reason to not have sex.”
Ida traced circles on Aoki’s skin. “You’ll be too tired to do anything, anyway.”
Aoki sighed, but then he couldn’t help but smile. “Thanks for protecting me.”
—
Ida was right.
Aoki did end up feeling horny, hyper-aware of his mate’s presence (not to mention…orher things that his omega would not shut up about).
But it was too much effort to move.
In the haze of heat, all he could register was Ida’s scent, the rumble of his voice, and the length of his body pressed against him.
“Souta,” Ida whispered against his skin.
It was actually enough to be with his alpha like this. Just basking in each other’s presence, in the safety of their nest.
“You’re perfect, Souta. I’m so lucky to have you. My omega.”
He’s a good alpha.
Aoki hummed in agreement. Maybe the lines were beginning to blur between his rational and primal thoughts, but he had never been more sure of anything in his life.
He told Ida as much. “You’re a good alpha. My alpha.”
Ida growled, and suddenly the alpha’s lips were on his own.
Aoki’s eyes fluttered shut in bliss. His omega didn’t even mind when Ida had to pull himself away, breathing harshly against Aoki’s neck.
No, he was grateful for whatever his alpha gave him.
Ida rested his forehead against Aoki’s. “You make it impossibly hard to resist you,” he murmured.
Mount me, his omega whined, jumping at the opportunity.
Fortunately, Aoki managed not to say it out loud.
He was sure that it was hard enough for Ida without Aoki having to tempt him.
Ida distracted himself by giving Aoki a back massage.
Aoki mewled in response, allowing Ida to trace the lines of his body, to sculpt him anew with his hands.
When Ida was done, Aoki peppered his face with kisses. “So good to me,” he slurred.
Ida chuckled. “Are you sleepy?”
Aoki sank deeper into the nest, eyes drifting shut. “Want to sleep,” he agreed.
“I’m glad.”
Aoki opened one eye to glare at his mate. “Hey,” he grumbled. “Are you tired of me already?”
“No, Souta,” Ida shook his head, smiling. “It’s a compliment when omegas are comfortable enough to sleep during heat. Heats make omegas restless or tense. If you can sleep, that means you feel safe.”
Aoki blinked, struggling to stay awake. “Of course I feel safe,” he mumbled against Ida’s bare shoulder. “You’re here with me.”
“Good night, my omega.”
Aoku felt so impossibly calm. He could only focus on Ida’s gentle breathing, his fingers carding through Aoki’s hair, and their combined scents.
Aoki fell asleep, warm and comfortable and safe.