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Orange and Lavender

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Genos paused in his chopping, flaring his nostrils as a touch of lavender and sandalwood flooded into the air. Saitama must have been back from shopping. Even from inside the apartment, Genos could smell the intoxicating scent of the alpha. It made him absently squeeze his thighs together, his gaze blank as he stared into the onions beneath his knife. Sometimes he would indulge himself in the gentle, aromatic smell, let it wrap around his senses, let his eyes flutter shut and let his mind wander.

But he would quickly shake himself of the sensations, mentally berating himself for his weakness. He had long ago accepted the fact that he thought of Saitama as more than his sensei and had also accepted that his feelings would more than likely not be reciprocated. Saitama had explicitly stated that he wasn’t into men or anyone, as it seemed to Genos. After weeks of being upset with himself, he realized he couldn’t help what he felt. He was in love with Saitama and being in such a close proximity to an alpha of such strength and dominance was not making his feelings easy to handle.

Though, he had to commend himself for having the self-control of a saint. He also had to thank Dr. Kuseno for giving him control of his facial expressions and for his inability to blush.

Genos, himself, was an omega, a trait that could not be removed no matter how inhuman he was. He experienced heats like any other omega and hated them just as much as any other omega would. He thought of it as weakness, an inability to control one’s self. Even though he knew that this process was entirely natural and couldn’t be helped, he didn’t like the sudden desire to be submissive, to give and give until he got what he wanted.

As both he and Saitama were unmated, they had long ago agreed to be separated when either one of their heats or ruts came to fruition. Geno would leave to stay with Dr. Kuseno whenever one of them got…instinctual. It was easier that way. It made it less likely for anything to happen that they would both regret. Genos had recently had his last heat around two or so months ago and Saitama wasn’t due one for another two as well.

It was rather unorthodox for unmated individuals who had no intention of mating to live together, especially an alpha and an omega. Though, Geno had long ago accepted the fact that neither he nor Saitama were conventional individuals. Besides, they made it work. The first few months living together had been some to get used to and Genos had to admit that he had gotten overwhelmed by Saitama’s strong scent more often back then. Nowadays, they were more comfortable around each other, at least that’s the way it seemed to Genos. They found a functionality in their lifestyles, an enjoyable friendship.

Though, as Saitama’s scent drew nearer and as the sandalwood made Genos swallow thickly, he couldn’t help but wonder about more.

Genos heard the door open and he quickly went about chopping the onions again, frowning at himself for that silly little laps into fantasy.

“Oi, Genos. I got the eggs but there wasn’t any discount ham. I got the date wrong on the coupon,” He could practically hear the frown in his sensei’s voice.  

“That’s fine. We’ll just go without it. Welcome home, sensei,” He said, casting a glance at the man over his shoulder.

Saitama grunted noncommittedly, opening the fridge and depositing the eggs into it. “I wanted to get some hot sauce too but it was too expensive.”

“I’ll make sure to remember to get some next time,” He replied with a nod, already creating a mental note.

“I also got you that sushi that you like.”

That brought a small smile to his face, a fluttery feeling touching his core.

Saitama straightened up and out of Genos’ peripheral. There was a shuffle of feet but it stopped. Lavender and sandalwood was overwhelming behind him and Genos furrowed his brows when Saitama made no move to step away. He could feel him at his back, his presence looming and slightly intoxicating. Genos had half a mind to turn around and ask his sensei if something was wrong but something was stopping him, not a hand nor an arm but something he couldn’t pin down.

It made his fingers tremble and his breathing hitch. He was squeezing his thighs together again, grip tightening on his knife. The air was thick with something. It made Genos fidget, steam vents threatening to release in response to his nervousness. However, suddenly, Saitama took in a deep breath, exhaling sharply. Genos nearly flinched when he felt it cascade down his neck.

The next thing he knew, Saitama was seated in front of the TV, flipping through the channels.

Genos frowned down at his vegetables. In all the months they had lived together dealing with each other’s pheromones, nothing like that had ever happened before.

He shook it off in favor of relieving the tension in the room and continued making dinner as if nothing out of the ordinary had occurred. Saitama-sensei appeared relatively normal though Genos couldn’t help but notice a tiny shift in his scent. It was perhaps more exotic, like that of a rainforest but that might have just been Genos overthinking things. Regardless, their hot pot was served at the table and dinner went about as normally as it always did, with casual conversation and talks of sales passing between them.

Bedtime rolled around and whatever had happened in the kitchen was behind them. They said their good nights and that was that.



Genos awoke with a start, gasping for air as an unbearable heat fell over him. He sat up abruptly, throwing his blanket off of himself as his steam vents worked to keep him cool. He took in several gulps of air but nothing seemed to help. The room was spinning and he could distantly make out the fact that it was light out. He squeezed his eyes shut, hands coming up to cover his face. The futon beneath him felt like too much, his clothes constructing. It was as if everything was coming at him at a volume of 1000.

He groaned as he tried to change position. However, he stopped himself, the fabric at his arms and legs feeling too raw. This couldn’t be another heat. It was entirely too early for one to occur. He was always organized when it came to monitoring his heats and he knew, he really knew that he wasn’t meant to have one just yet. He had never heard of anyone having a heat so many months earlier than they were supposed to.

Suddenly, a beautiful, intoxicatingly enchanting scent touched his nose, making him moan and arch his back. It surrounded him, bathed him in a torrent of need and desire. He let it fill him, inhaling deeply so that every inch of him was touched by it. It made his limbs tingle, made him rub his thighs together roughly and wish for Saitama to claim him then and there.

That last thought brought him back to his senses. He lowered his hands, daring to turn and look at his companion. The alpha in question was lying on his back, eyes wide as he stared up at the ceiling. His chest was rising and falling so slowly that Genos had to make sure he wasn’t hallucinating anything. His jaw was locked tense, lips pulled into a tight line and brows drawn together.

“I’m s-sorry…Sensei.” Genos was a breathless mess. He bit his lip to stop another moan from pouring out. “I-I don’t know…what…what…” He trailed off as a shiver ran down his spine, steam fluttering from his arms.

Saitama wordlessly sat up, squeezing his eyes closed for an ungodly amount of time. He swallowed, his Adam’s apple bobbing up and down. Genos found himself mesmerized by the motion, by the broad line of Saitama’s shoulders, by the way his muscles looked against his pale skin. His shirtlessness was an unneeded though not entirely unwanted addition to the onslaught of sensations and feelings Genos was currently being bombarded by.

Finally, the alpha spoke, voice surprisingly steady as he turned to look at his companion. “Uh, are you…”

Genos hummed dreamily at the sound of his voice but covered his face again, embarrassment coming out of him as puffs of steam. “I shouldn’t be. Not for a-another…another few months. I—”

He broke out into a series of gasps, squeezing his thighs together and bringing a hand to his chest. He shuddered as another wave of heat tumbled over him. He threw his head back, eyes sliding shut as he arched his back again.

Mortified and overwhelmed, he straightened back out to find Saitama staring right at his neck, something dark and hungry deep within his eyes. There was a shift in his expression, a twitch of his jaw, an exhale. It made Genos shiver, biting his lip to keep from moaning again. He needed to say something, anything but what came to mind was a load of gibberish and desperation.

Take me.

Hands, need you

Claim me.

So close, smell captivating

Ruin me.

Love me.

Genos let out several deep breaths as he pushed himself upward, staggering to his feet rather gracelessly. “E-Excuse me,”

He ducked into the bathroom before Saitama could say anything, sliding the door shut with a little too much force. He wouldn’t dare look at himself in the mirror. He needed to focus or at least get control of himself. He and every omega in existence knew the best way to get over a heat and it involved someone else, more specifically an alpha. Of course omegas could handle themselves during a heat but that typically extended it by an additional day or two.

Genos couldn’t ask Saitama to…help him. He just couldn’t. If he did and Saitama helped, his dreams would have become a reality. But at what cost? He didn’t want to ruin their friendship. He didn’t want to take advantage of the situation and inevitably manipulate Saitama into doing what Genos wanted.

The cyborg nodded to no one in particular, resigning himself to handle this heat as best as he could without compromising his morals and his friendship with the greatest man he had ever known.

Besides, Saitama was perhaps the most self-controlled person on the planet. Genos knew he wouldn’t do anything or at least wouldn’t do anything without asking first.

Genos nodded again, reaching for the doorknob and leaving the room. He had to support himself against the wall as he made his way back into the living room and he stumbled, causing his pants to rub up against the panel concealing his, well, dick. He had to remind himself to thank Dr. Kuseno for the discrete paneling.

Rounding the corner, Genos found Saitama standing in the middle of the room, body turned towards the window, rubbing his hands together. The cyborg couldn’t help dragging his eyes down the man’s back muscles, mesmerized by taut skin. Saitama’s pajamas were a tease, resting ever so perfecting against his hips, hiding the rest of him from sight. Genos could only imagine what it would feel like to have those strong, dangerous arms surround him, lift him up and press him against a wall, tear his clothes asunder.

Genos shifted to lean against his support, knees trembling beneath him. His lips were quivering, dying to breathe out his every wish and desire. He settled for biting those treacherous lips closed, a low hum a result of that battle. Steam puffed out at the sound and Genos pressed his head against the wall in shame.

Saitama finally turned around, looking him up and down before opening his mouth to speak. He stopped himself, eyes flickering between his roommate and some other corner of the wall. “Do you need like some water or anything? You’re looking a little toasty there, bud.”

Genos swallowed, shaking his head as he replied, “I…I’m fine. Just-just let me…” His knees finally gave out and he fell to the ground, groaning as he did. Saitama stepped forward to help him but he froze suddenly, furrowing his brows as he frowned at the table. “Sensei? Are you alright?”

The man in question blinked several times, a deep breath falling from his lips. He pressed a hand to his chest, eyes widening as he blurted out, “Oh, shit.”

Genos watched in confusion as his sensei’s shoulders prominently rose and fell as he breathed in and out, the intervals becoming shorter and shorter until he was downright panting. Color touched his cheeks, a low growl bubbling out from deep within his throat.

Genos felt the sound travel down his spine, fluttering his eyes and bringing a wicked smile to his lips. The alpha’s scent slowly shifted into something thicker and heavier, like the smoke from a forest fire.

“This isn’t supposed to happen now.” The man breathed out, eyes instantly seeking out his companion.

Genos knew that look. He had seen that in dozens of other alphas who had the unfortunate chance to go into heat on a crowded street. It reflected a craving to devour the first thing in sight and that was typically an omega. However, there was something else in his eyes, something deeper, something akin to what looked like fear.  

The two stared at one another for a silent moment, neither moving towards nor away from each other.       

That desire was back again, bubbling deep within the pit of Genos’ stomach. It made him want and need, yearn for the man in front of him. He wanted to beg, scream, crawl to Saitama’s feet and beg for him to claim him.

A dizziness touched his mind as he struggled to breath, hands digging into the wall, craters beneath his palms. He swallowed, a puff of steam rolling from his lips as he exhaled. Saitama’s gaze followed it down, body tense and shoulders rigid.

Just let him do it.


You know what you want.

Genos shook his head, shattering the thought and pushing himself upward. “I-I’ll go.”


“I have to.”

“NO!” He halted halfway towards the door, entire body frozen. It was as if he had just fallen into a lake of ice water and if he could, he’d have goosebumps. Saitama’s voice had vibrated between Genos’ circuits, nearly throwing him to his knees again. “You’re not leaving.”


“Not like that,” He said softly, almost too quietly.

Genos frowned at the door, knowing Saitama was right. It was ill-advised for someone to be outside during a heat. Dr. Kuseno was also away at a convention so staying with him was out of the question.

“I could stay with Mumen,” He tried. Betas weren’t affected by the pheromones of their other counterparts.  

“You’re staying here.” There was something beneath the waves and timbre of Saitama’s voice but Genos couldn’t pinpoint what it was.

“I understand, Sensei.” He replied, letting out a shaky breath and rolling his tense shoulders. He turned around to face the alpha, meeting his gaze meekly. “This isn’t going to be easy.”

“We’ll make it work like we always do.” Saitama’s hands were balled into tight fists, knuckles painfully white. “We’ll just—” He tipped his head back, eyes finding the ceiling. He swallowed and Genos watched the process hypnotically: chest rising, shoulders dipping back, Adam’s apple bobbing. “Ride it out.”



And they did manage to coexist for the next two hours. They were often on opposite sides of the room, Genos to the kitchen and Saitama to the living room. Those two hours were characterized by one of them occasionally ducking into the bathroom or to the balcony. They had to keep the balcony door open due to the steam near constantly rolling from Genos’ shoulders and it made the room a few degrees too warm. Saitama had raised the volume on the TV either to drown out his own labored breathes or Genos’. The cyborg still had yet to figure out who’s.

Genos often found himself dropping to his knees more often than he was on his feet and at one instance he had thought he had ruined the floor by the door. The near frequent moans or hums weren’t helping his crumbling composure either but he was glad to know that Saitama wasn’t doing any better. He had broken six things in the span of the first hour and he was on his way to the thirteenth if he kept holding the remote like that.

He had said that this amount of destruction was normal during his ruts and Genos had grown used to coming back from Dr. Kuseno’s after Saitama was over one to find much of the apartment in disrepair. Though, there were always defining features of one’s heat. Genos’ just so happened to be weak knees and overheating.

At that thought, he placed his hands on the counter to steady himself, eyes glaring daggers into the sink.

He took in two sharp breaths, a warning message flashing briefly about his oxygen levels. He shook it away absently, glancing over at his alpha companion. Sitting cross-legged at the table, Saitama’s attention was focused entirely on the manga in his hands. Though there was a prominent frown at his lips and his brows were drawn downward.

A waft of lavender and sandalwood touched the air and Genos hung his head in torture. Two more breaths of air and he squeezed his eyes shut. Something buzzed in the pit of his stomach, vibrating throughout him pleasantly, a long moan falling from his lips. That’s when he felt it, slick trickling down the inside of his leg. A puff of steam bellowed out at the discovery and his head shot upward.

He stepped back, cringing at the wetness. He struggled to breathe, hands coming up to his chest, thighs pressing together, knees threatening to give in. Several error messages flashed across his eyes but he couldn’t focus on anything, the beautiful, tantalizing smell of Saitama taking all of his attention. Another message popped up, something about hyperventilation.

He was dizzy, the world spinning above and below him. Saitama had said something, probably to ask if he was alright, but Genos couldn’t speak, the air rushing from him every time he tried to. An unbearable heat permeated throughout him, his temperature rivaling that of a newborn star.

Then, he was falling, backwards, darkness finding him the moment his head hit the ground.



Saitama was up the instant Genos fell. A primal instinct washed over him, an intense and overwhelming desire to make sure the omega was alright. He had nearly ripped his manga to pieces in his haste to stand up. But he didn’t know what to do. Was Genos dead? Broken? He could see the cyborg’s head and shoulders from where he was standing but the rest of him was hidden behind the kitchen divider.

Saitama wanted to step closer but he needed to maintain control. The closer he got to the omega, the more he would be able to smell him, that oily, citrusy, glorious, hypnotically enchanting, marvelous—

He threw his hands into the air with a grunt, feeling his pants getting tighter yet again. He could smell Genos’ slick from here, just as delectable as the cyborg himself.

As the day progressed, it was getting harder and harder for Saitama to control himself and the spine tingling noises Genos would often make did very little for his composure as a gentleman. He would not force himself on the cyborg no matter how out of it either of them were or would be for the duration of their torturous heats.

He should have let him go, perhaps to Mumen’s or King’s. Just someone who wasn’t another alpha. But something possessive and greedy within him felt disgusted at having another person near Genos during his heat. It had sickened him. His selfishness kept the omega here with him, tormenting them both with their mix of pheromones.

Saitama knew his presence was doing nothing to quell the heat Genos was feeling because it was just the same for him. An omega in heat would often make an alpha fidget and get all hot and bothered but it being Genos and during his own rut was not doing him any favors. He had never heard of unmated individuals going into heat at the exact same time. Perhaps this was punishment for getting that expensive pack of sushi yesterday.

But that didn’t matter right now. He had to make sure the omega was alright. Then he could have his own pity party somewhere else. Maybe the bathroom.

Saitama pinched his nose, rolled his shoulders, and stepped towards his companion. He could still blatantly smell the orangey scent of the omega and his slick was becoming more apparent as he moved closer. Saitama let his hand curl against the corner of the counter as he peered down at Genos, sighing in relief when he discovered he was alright.

His chest was very slowly rising and falling and his core was still bright and beautiful within his chest. Saitama could see it bleeding out from beneath the fabric of his shirt (he had forgone his apron earlier) and so long as that was shining, Genos was fine. He had to mentally praise himself for remembering that little fact. Dr. Kuseno hadn’t of been entertaining when he explained it one evening.

Genos had fallen rather gracefully despite everything. He was supine, his arms angled away from his body. His eyes were shut and his lips were parted ever so slightly.

Saitama’s gaze followed down the curve of Genos’ neck and down his body, mesmerized by the mix of metallic tendrils and smooth material lining his shoulders and arms. The alpha knelt down, leaning closer as he inhaled deeply. He hummed at Genos’ sweetness, that tangy citrus making his mouth water. There was a quiet sizzling sound coming from his metal parts and when Saitama hovered his hand over the cyborg he could feel a slight heat radiating off of him. However, it wasn’t unbearable. To him, it was like any old heater.

After a mesmerizing moment, Saitama found himself saying, “He’ll never love you back.”

Frowning, he blinked at himself. He let out a defeated sigh before moving to lift himself up.

But if he did?

His movements stilled, eyes falling back down to the omega.

Genos was too handsome to describe. He was just…Genos. Kind, strong, selfless, ambitious. He was the perfect human being. Being near him was a privilege. People should be lining up just to gaze upon his beauty in awe. And somehow Saitama was lucky enough to live with this…this…god? He was also lucky enough to have fallen in love with him. Or unlucky to, depending on his mood. He knew it was impossible for someone like Genos to ever be in love with someone like himself. He was the exact opposite. Unmotivated, lazy, egotistic. Genos would never love him.

But if he did? If he did, Saitama’s entire life would be more meaningful. The stars would be brighter, the sky more beautiful. Perhaps he would actually be happy.

He finally noticed his fingers running through Genos’ hair. His first reaction was, not to pull away, but to lean closer, fill his lungs with the smell of the omega in heat. So, he did. He placed his other hand on the cyborg’s chest, leaning down so that he was hovering above his collarbone. After a glance back up at Genos’ face, Saitama buried his nose into the curve of his neck, breathing in everything that was the omega.

He smelt of oil and citrus, a touch of cinnamon threaded between the two. He was delectable, a warmth spreading throughout Saitama from his head to his toes. The alpha grinned, pressing closer, a growl bubbling up from within his chest. He felt something primeval slither into his mind, darkening his thoughts and slowing his breath.

“But if you did?” He whispered against him, tongue flicking out to lick a long strip up the curve of Genos’ neck. “I’d give you everything.”

A sharp intake of breath startled Saitama out of his trance and he snapped backward as if he had been slapped. He was by the TV in the blink of an eye, breathing heavily. He had thrown himself to the wall with so much force that a shallow crater fitted at his back. Sweat touched his brow and he found his pants uncomfortably small. He touched a hand to his chest, his heart ready to burst. He was warm, too warm, mind racing as he thought of every single thing he wanted to do to Genos. Guilt. Shame. Humility. All ran through him like a lightning bolt, shocking him into place. He was fighting with himself: let nature be nature or don’t ruin your relationship with your best friend.

Another sharp breath was accompanied by the movement of arms, twitching as motor control returned. Genos opened his eyes, blinking up at the ceiling for a brief moment. And in that moment, Saitama hurriedly and quietly repositioned himself at the table, taking his manga into his trembling hands and fixing his gaze on a page number. 36.

“Sorry, dude. I didn’t wanna touch you so I kinda had to just leave you there.” He had to raise his voice above the volume of the TV.

Genos’ words were slow and unsteady when he said, “I understand, Saitama.”    

Saitama? Saitama? Saitama?! Why on Earth—Of all the things to—

A growl and the manga he was reading was torn in two, right at the spine. Saitama shook his head frantically with a groan, reaching behind him to grab a pillow. He screamed into it as loud as he could, his knee moving up and down as a result of his unease. He shot upward, kicking the table in his haste. Face still in the pillow, he managed to find his way onto the balcony, screaming into his trusted companion once he felt the cool air touch his arms.

Once he was spent, he dropped the pillow to the ground, letting out a huff of frustration. His entire body was sizzling, screaming for him to take and conquer and do all the things he would very much want to do to Genos.

He bit his lip, eyes fluttering as he felt instinct and nature scream for him to claim the unmated omega.

He would love to. He really would. But he knew, he just knew that Genos would never let him or want him to. Genos’ affection for him went as far as a curious fascination, a man who he thought could teach him the secret to tearing the sky asunder.    

Oh, but that voice. The way it caressed and touched each syllable of Saitama’s name was sinful. Downright dirty if you asked him. And the quiver? The waver in his voice? It was like something out of an anime. A hentai, to be honest. And Saitama would very much like it if this entire situation ended like one.

He cleared his throat, hands gripping the railing, the metal bending beneath his fingers.

He wouldn’t risk it. Not like this. He wanted to confess his feelings with a level head. If he ever did.

He straightened up, rolling his shoulders, reigning his features in, readying himself to go back inside. He could barely handle a few hours of this. How was he supposed to last a few more days?

Saitama slapped his cheeks several times before going back into the house, citrusy goodness instantly biting at his nose. Genos had stood back up, having essentially returned to his original position facing the sink. However, his hand was resting against his chest, just beneath his neck, a pensive expression coloring the rest of the image. Though, suddenly, his head jerked at an angle and he blinked as if a thought just came to mind. He furrowed his brows as he looked over at his alpha companion.  

Their eyes met as Saitama walked in but he quickly looked away, hurrying to stand in front of the TV. Saitama could feel a flush coming to his cheeks and he sighed, deflated, reaching down to grab the remote. He aimlessly flipped through the channels but everything that came on annoyed him to no end, each noise making him growl angrily. It was all too loud, too much, not what he needed, not what he craved.

He knew just what he wanted to hear and who he wanted to hear it from.

He turned the TV off, staring at himself on the darkened screen.

He was already too far gone now, wasn’t he? It was too late for him. He knew he was going to hell for what he was just about to do. He knew and he didn’t care. Though, maybe he cared a little. Just a tiny bit. Actually, no. No, he didn’t.

If Genos said yes, then, well—

A crack and shatter erupted, the remote crumbling to pieces in Saitama’s hand. He sighed before shaking his hand of the debris. He set his shoulders and, fueled by a primordial sense of purpose, walked into the kitchen.

He stopped behind the omega, a wash of his scent flooding into Saitama’s lungs. A growl was ready to erupt from within him, rumbling deep within his vocal cords. “Genos,”

His voice made the cyborg tense. A shaky breath left him before he turned around, eyes locking with Saitama’s. There was recognition deep within those beautiful golden irises, acknowledgement, understanding, as if he knew exactly what was running through Saitama’s mind. Perhaps he had always known, struggling with the same things himself.

Maybe, just maybe, Saitama wasn’t alone in this.

He opened his mouth to speak but was cut off by the cyborg whispering, “We shouldn’t.”

Saitama swallowed thickly, finding the strength to ask, “But do you want to?”

It was a while before Genos said anything. Every silent second that passed was torturous, each minute ticking by with a slow sort of sadist delight. The omega looked away, lips trembling with all the power that they held. Finally, finally, Genos nodded, a frantic up and down motion that was magnificent nonetheless.

Saitama knew that if they continued, they would never be able to go back to what they were. But, he knew he was already decided, knew it the moment he scented the omega.

And when Genos looked back up at him, meekly, expression that of nervousness and uncertainty, Saitama knew then too. He was doomed.

Tomorrow’s him would just have to deal with the consequences.

“Fuck it.”

Genos’ face morphed into that of complete and utter confusion for about 1.3 seconds before Saitama was on him, capturing his lips with his own. They were surprisingly soft and realistic, moist and heavenly. And Saitama was pleased to see Genos reacting so pleasantly, moaning and clutching his arms desperately. He was kissing back rather frantically though Saitama wasn’t exactly the epitome of patience and slowness at the moment either, both overwhelmed with heightened senses and pent-up emotions.

The smell of citrus was near overbearing but it sent a luscious chill down Saitama’s spine, urging him to press closer, his erection painfully straining from within his pants. He slid a hand beneath Genos’ shirt, vaguely wondering if the cyborg could even feel it. Though, the way he hummed against his lips, told him that he could.

That also made Saitama wonder if the omega had anything…down there that would make this experience mutually pleasurable. He must have given that he still went through heats. The genius Dr. Kuseno wouldn’t have left him hanging in that department, would he?

“Do you…have anything…uh…for…” He couldn’t even finish the sentence between kisses before Genos nodded hurriedly, fingers digging into the skin at his ribs.

That was enough for the alpha, fumbling with the omega’s shirt and finally managing to remove it after coaxing Genos’ arms up. He ducked down, kissing and nibbling at the material at Genos’ neck and eliciting beautiful noises from the man, music to his ears. He returned to that same spot he had licked earlier, threading his fingers back though Genos’ hair and pulling roughly, tilting his head upward.

The cyborg was a mess beneath him, steam radiating off of him as he squirmed, hands roaming up and down Saitama’s back, fire beneath his fingertips. There was a pop and a hiss and Saitama instantly thought that he had broken something. However, at the long sigh that fell from Genos’ lips and the sudden press of something against Saitama’s thigh, he could put two and two together. To test it, he pushed Genos’ legs apart, rubbing his thigh against his erection and pulling a delicious moan from the cyborg.

Saitama grinned as he licked a long strip from Genos’ collar up to his ear. It tasted strange just as it had earlier but it was not unpleasant. It was actually turning him on. 

“Sensei, please,”

Oh. Those words, with that voice, in this situation?

It made something stir within Saitama’s heart, made him giddy. A deep, primal instinct overtook him, filling his bones and his muscles and his senses with an undeniable, barbaric desire to claim.

He unbuckled Genos’ belt, almost ripping it off in his haste. He motioned for the cyborg to remove his jeans, stepping backward to give him room. As Genos divested himself of his rather tight clothes, he paused, hand lifting his foot out of his last pant leg. Saitama was just about to ask him what was wrong until Genos sunk to his knees, hands tugging at the waistband to Saitama’s pajamas.       

The alpha could only watch as his pants were slid down, erection springing free, the fresh air making him shiver. Genos simply stared, shifting on his knees, more slick trickling down his leg, the smell near intoxicating at this distance.

Finally, with a glance up at Saitama, the omega licked the tip, drawing a short gasp from the man above him. He continued, tongue running up the length of his member before taking him into his mouth. Saitama dipped his head back, sighing, threading his fingers through the cyborg’s hair as the omega began a slow, sensual pace, savoring every inch of him. Genos’ mouth was deliciously warm and incredible, his tongue a masterpiece.  

Saitama unconsciously tugged on Genos’ hair, urging him to go faster, his wish being granted only seconds later. His fingers tightened within beautiful honeyed strands, breath growing more haggard by the minute.

He groaned, still in disbelief at what was going on. He couldn’t wrap his head around it. It was as if he were viewing this all from over his own shoulder, reality having not found its way back to him yet.

The omega shifted again, a hum bubbling up from his throat, mirroring that of a constricted moan, the sound reverberating throughout every bone in Saitama’s body. He looked down and bit his lip at the sight before him. Genos’ eyes were screwed shut, brows furrowed in concentration as his head bobbed, hand between his legs, palming as his own neglected erection. Steam puffed out as he squeezed his thighs, shoulders stuttered through a shiver.

Genos made another noise and Saitama mirrored it, the feel of the cyborg’s mouth and the beautiful sight before him bringing him closer and closer to the edge. He let out a heavy breath, eyes fluttering as Genos went faster. He hunched over, hand now a fist within the omega’s hair. Genos was just as close by the look of it, his hand at his own cock picking up its pace.

“Look at me.” Saitama breathed out.

Two luminous eyes popped open, meeting Saitama’s, the sight making him twitch forward into Genos’ mouth. The cyborg grunted in surprise and the alpha was about to stutter out an apology before Genos lowered his hand to his lap and tilted his head up, widening his mouth as he looked up at Saitama expectantly.

The hero blinked at him for a quiet moment before his lips quirked up into a smirk and he adjusted his grip on Genos’ hair. He started fucking into the cyborg’s mouth, throwing himself into a brutal yet cautious pace.

Genos moaned into each thrust, hands growing frantic between his thighs. His slick was driving Saitama crazy, the scent heating his veins and feeding the rising torrent within his belly. Eyes never leaving the cyborg’s, Saitama came with a growl, pulling out of Genos’ mouth reflexively. Cum peppered the omega’s chin and chest as he shuddered through his own orgasm, back arching as a breathless moan tumbled from his lips.

They stared at one another as they regained their breathing, silent save for their labored gasps and Genos’ humming machinery. The heat induced haze was nearly gone from Saitama, having satiated itself with his most recent release. Though, only very nearly.

So nearly that he found himself saying, “You’re gorgeous.”

Genos could only blink at him as he dropped to his knees in front of him, steam puffing out of him in embarrassment. Saitama brought his hands up to cup his face, still sticky with the alpha’s cum. Saitama kissed him, tasting himself at the omega’s lips, a possessive growl thundering from within his vocal cords. He grinned as Genos kissed him back, the cyborg’s hands finding his shoulders, fingers still slick with his own cum.

“I did good, Sensei?”

“Incredibly,” Saitama exhaled, nipping at the material at Genos’ neck. “You’ve destroyed ‘Sensei’ for me, by the way.” 

“Is that bad?”

“Keep using the word and we’ll find out.”

“Yes, Sensei.”

Saitama sighed into a chuckle, fingers travelling down the omega’s back and settling at his hips, pressing circles into his waist.

After a few moments of enjoying each other and their partially satiated heats, Genos asked, rather quietly, “May I make a request, Sensei?”

“Sure, if you ask nicely,”

“I want you to fuck me.” A firm press of Saitama’s hand and Genos added, “Please.”

The alpha’s lips twitched into a smile, a fuzziness touching his heart and mind. He tightened his grip on his companion before standing up, letting Genos find his footing before letting go. He gestured to the counter, causing the cyborg to stare at him in confusion. Saitama sighed, pushing the omega until he was standing in front of it. He spun him around, pressing a hand against his shoulder until he was bent, flush against the countertop, back beautifully curved, ass begging to be fucked.

Saitama bit his lip, fingers slowly travelling down Genos’ spine and settling just above his tailbone. He kicked the cyborg’s legs apart, moving forward until his newly and painfully hard cock was pressed between Genos’ cheeks, slick so sweet it was going to rot Saitama’s teeth. He leaned forward, chest to back, mouthing at Genos’ ear as he ground against the omega’s twitching entrance, drawing a needy moan from him.

“What did you want, Genos? You have to be more specific,” He whispered, straining to keep himself composed. The heat was beginning to come back, begging him to indulge in the masterpiece beneath him.

“I want you…to—” He moaned as Saitama ground against him again, hands desperately gripping at the ends of the countertop. “F-Fill me up.”

“Oh,” He wasn’t expecting that kind of language from Genos of all people but it wasn’t unwelcomed and, judging by the way Saitama’s entire body ignited at the words, they weren’t unwanted.

“Stay down,” He whispered as he pushed back up, fingers ghosting over Genos’ entrance, slick coating each digit instantly.

He pressed one in, barely any resistance meeting him as he pushed further in. Genos dropped his head to the counter, a pleasant sigh escaping. He wiggled his hips and Saitama pushed another finger in, scissoring them both as he struggled to find the cyborg’s would-be prostate.

He had to have one or at least something like it. Hopefully, he did. Though, Genos obviously displayed the fact that he could cum so if he didn’t have a prostate, Saitama would settle for stimulating his erection. Perhaps—

There it was, a bundle of material just as smooth as Genos’ neck. Saitama circled it with his finger, making the omega jolt, steam puffing out of him as he moaned loudly. The alpha grinned, pressing against the muscle each time he pushed in, Genos near melting beneath him.

“Please,” Genos gasped. “I n-need you.”

Saitama pulled his fingers out at that, coating his member in that beautiful slick before sliding inside, fully sheathing himself within him with ease. They both groaned at the sensation, Genos the fullness, Saitama the heat. The alpha had to will himself not to cum instantly, citrus, cinnamon, sweetness and pheromones making his mind cloudy with lust. He could feel himself so close already and he needed to bring himself back down or this venture would be over before it began. And, oh, did Saitama want to savor every moment of this.

He looked down, licking his lips as he watched Genos push his hips backward, a needy moan touching the air, his back a beautiful curve, feet nearly off the ground. And Saitama couldn’t wait, sliding out and pushing back into him rather roughly, a brutal pace which Genos tried to match each time he thrust forward. Screw savoring. Saitama wanted Genos now.

The alpha grunted, hands tightening around the omega’s waist as he snapped his hips forward, angling himself so he’d hit that sweet little spot every time. It made Genos an instant mess beneath him, clawing at the counter to keep him steady. He could barely form any words, much of them too breathy or jumbled to understand and that only turned Saitama on more. The stoic, reserved, and quiet Demon Cyborg was reduced to moaning loudly with each thrust, begging to be fucked harder and faster.

It made the alpha growl, the sound a savage mixture of lust and a possessive desire to claim the omega.

Without breaking pace, he leaned down, gripping a handful of Genos’ hair and tugging, pulling the omega’s head up to bare his neck. He pressed his lips to his ear, biting and licking his way down until he was mouthing at the curve. From here Genos sounded so beautiful, every hitch in his breath, every glitch in his voice could be heard with lovely clarity. He could tell the cyborg was close, his moans growing more frantic with each thrust and his begging more incomprehensible. And Saitama was too, his grip painful in Genos’ hair, pulling perhaps a little too roughly.

Finally, Genos inhaled sharply, freezing in place as he came, exhaling with a tremble as he cried out, spilling onto the counter. He tightened instantly around Saitama and the alpha felt something erupt from within himself and before he knew what he was doing, he bit down hard on Genos’ neck as he spilled into him, his knot forming within the omega.

Genos moaned at the feeling, steam flooding out as he twitched roughly before going limp, entire body falling motionless. Saitama didn’t even have time to react before the cyborg was back up, gasping for breath as he steadied himself on the counter. He wiggled his hips and Saitama grunted, placing a firm hand at his back to stop the motion.

“Are you ok? You kinda passed out, I guess?” The alpha said after he settled.

His companion nodded. “I’m f-fine. I was overstimulated. My mind couldn’t keep up with my body so I shut down briefly. It happens sometimes especially during heats.”

“Hm,” Saitama murmured as he absently ran his fingers down Genos’ side, drawing a shiver from the cyborg.

“I never knew how…effective assistance was during one’s heat.”

He chuckled at the way Genos phrased it but ultimately said, “I’m feeling better already.”

“Me too,”

Neither said much after that, not really wanting to discuss what just transpired. Saitama didn’t even know what to say. Sorry for using you during my heat? Thanks? We’re still friends right? He didn’t know where to start and if there even was a start. What did Genos think about all this? He could ask but he didn’t want to get his hopes up only to have them come plummeting to the ground.

Hey, you know we just had heat and pheromone induced sex but I really liked it and I really like you.

No, that sounded dumb. Saitama sighed in defeat, letting himself stay silent as he waited for his knot to soften. At least things weren’t awkward. Genos hadn’t shriveled up into an embarrassed ball of self-hatred and weakness yet. Though, that might have been because he literally couldn’t right now.

As Saitama slowly pulled out of his companion, he sighed, taking in the sight of Genos bared before him, committing the very image to memory. And he couldn’t help but lick his lips as he watched his seed trickle down Genos’ leg, hoping that he’d get to do this again really soon.    



And apparently, really soon turned out to indeed be really soon. They had decided to take advantage of the lull in their heats by cleaning up and changing their clothes. After a half hour of avoiding the elephant in the room, Genos managed to finish up dinner, making simple bowls of udon given that his attention span was still severely lacking. Saitama was seated by the table, patiently waiting for the omega to bring it over.

He looked down at his hands, frowning as his mind once again relayed the day to him. He really should say something to the cyborg. He just didn’t know where to start.

It also didn’t help that Genos wasn’t saying anything about it either. The teen was the king of honesty and bluntness and yet here he was saying absolutely nothing. Did he just want to forget about it?

With furrowed brows, Saitama sighed as Genos stepped out of the kitchen, noodle bowls in hand.  

“I believe there will be a sale at that grocery store in city D in a few days. Up to 70% off. Perhaps we could—”

The alpha looked up at the halt in speech to find his companion stopped just outside of the kitchen, blinking at himself, eyes straight ahead. Genos let out a long stream of air, lips quivering near the tail end of the breath. A tremor ran up his spine causing him to drop the bowls, glass shattering as he moaned, sugary sweet slick touching the air one more beautiful time.

Saitama couldn’t hide his grin, his own heat sliding home with an enthusiastic vigor. When Genos met his eyes shyly, the alpha could do nothing but hold out his hand.

After a moment’s hesitation, the omega took it, settling down onto Saitama’s lap, knees either side of him. The alpha was happy to note that his erection settled against his own quite nicely. Though, he wouldn’t meet the alpha’s gaze, hands dropping down to fiddle with the bottom of Saitama’s shirt.

“I’m sorry,” He whispered.

Ah. There it was, that Genos-style self-defeatism.

“You don’t need to apologize for this. Besides,” Saitama tilted the omega’s chin up, capturing his lips with his own before murmuring, “I wasn’t hungry.”

“I feel like I’m using you, Sensei.” He said softly, taking in two breaths of air as he shivered.

Said sensei grunted noncommittedly, sliding his fingers beneath Genos’ shirt and pulling it off in one swift motion. “We’re using each other.”

He didn’t exactly want to phrase it in that way but until he knew definitively what the cyborg’s feelings were he’d settle for that, indifference. It would make it hurt less if Genos really was just using him.

The omega remained silent as he took his turn pulling Saitama’s shirt off. He moaned suddenly, twitching forward, the friction causing Saitama to make one of his own. Genos arched his back, his head falling backwards. In this position, Saitama narrowed his eyes at a particular spot at the omega’s neck. Realization made him flinch, taking in a sharp breath of air.

Genos straightened back out, tilting his head at him. “Sensei?”

“I didn’t mean to.” He whispered, shaking his head. “I’m sorry. I-I was caught up in the moment. I didn’t even ask—I’m so fucking stupid.”

“I don’t understand.”

“This,” He touched his fingers to the spot, frowning at the tiny indentations, like that of a bite mark. “I did it without asking you. You must think I-I’m—”

“I don’t mind.”

“What?” He looked up only to find Genos smiling at him, a warm clarity in his eyes despite both of their raging hormones.

“I don’t mind as long as it’s you, Sensei.”  


Genos shook his head fondly, a short laugh falling from his lips. “I love you.”

Saitama stared at him silently, eyes wider than the moon. He was speechless. He really was. His mind was slowly wrapping around what was just said, reality finding its way back to his consciousness.

Perhaps he was too silent for Genos began shifting in his lap rather nervously, furrowing his brows as he lowered his gaze to his lap.

“Maybe I shouldn’t have—”

And Saitama kissed him, swallowing the words down with the gesture, hand finding its way into the cyborg’s soft hair. He flicked his tongue out, kissing the omega breathless before reluctantly pulling away. He grinned at the way one side of Genos’ hair was stuck up.

“I love you too, Genos.”

“…I thought you didn’t like men.” He asked after taking a moment to catch his breath.

Saitama shrugged. “I say a lot of things I don’t mean. But I did mean this. I really love you. I just never told you because I was afraid you’d never love me back.”


“Come on, man. You’re you and I’m just…me. I’m not an interesting guy.”

Genos looked as if he’d just been sucker punched, mouth opening and closing as he shook his head in disbelief. “Sensei—”

“No. No, I know what you’re gonna say. You’re gonna go off on a tangent about how awesome I am and we’re gonna be sitting here till the wee hours of the morning when you finally finish.”

With a sigh, Genos brought his hands up, fingers caressing Saitama’s cheeks as he pressed a kiss to his forehead. He whispered, “I think you’re amazing, Saitama.”

The alpha stirred at the use of his name, that same wash of lust and possessiveness falling over him just as it did after Genos had passed out. The citrus and cinnamon in the air suddenly smelled too good, sugary sweet slick an overwhelming and welcomed addition. All of it made Saitama growl, a sound that rumbled deep within the depths of the earth until it thundered back out of his mouth, electrifying the air.

He urged the cyborg to his feet, gesturing for him to take his pants off as Saitama did the same. Genos seated himself back down onto Saitama’s lap, pressing their erections together.  

“I think,” Saitama paused, hand traveling down Genos’ spine. “You’re mine now.”

“Really?” The omega smiled, sighing pleasantly and arching his back as he felt Saitama’s fingers slide into him.


“I’m…glad,” He breathed, moaning as Saitama added a third finger.

The alpha smirked, licking at Genos’ mating mark. “Me too,”

They continued like that for quite some time, slow and unhurried movements despite the rising urge to satiate their heats. It was quiet save for their heavy breathing, the outside completely silent, the world simply letting them enjoy one another. And indeed they did, a more lighthearted mood falling over them compared to earlier in the day. 

Though, their languid, sensual movements could only last for so long until one of their heats urged them to go faster.  

“Sensei…” Genos whined, wiggling his hips, steam puffing out from his vents as he gasped.

“I know,” Saitama murmured, sliding his fingers out and resting his hands at the cyborg’s waist. “Go ahead.”

Genos lifted himself up and onto Saitama’s cock, slowly letting it slide into him as he settled back down. He hummed the moment it was fully inside him, head thrown back, arms wrapping around the alpha’s neck. He started moving as Saitama kissed him, moaning into his lips, nearly bumping their heads together at a sudden twitch in his movements.

Saitama merely smiled against him, one hand finding its way onto Genos’ upper back and the other curving around his ass. He inhaled deeply, letting all of the omega fill his lungs, groaning as he felt slick drip onto his leg. Genos smelled both sweet and tangy and Saitama liked to think that it mirrored the fact that he was both human and robot.

To add to everything, the position they were in allowed Saitama to see what he couldn’t earlier. He was mesmerized by the expressions that crossed the omega’s face, Genos’ brows furrowing and relaxing, his lips quivering and parting to breathe, head lolling and dropping back as he moved up and down. Pure pleasure and ecstasy was written across his face and Saitama couldn’t help but feel it too, coursing through his veins and thrumming throughout his bones.

He matched Genos’ pace with his hips, thrusting upward as the cyborg came down, hitting him in just the right spot.

“There you go, Genos,” He breathed out.


Yep, that word was ruined.

“You’re close. I can feel it,” He murmured.

He really could. There was a tension in the omega’s legs, his body feeling increasingly hotter. He was tightening around the alpha, movements more unsteady and rushed, his breathlessness making him unable to say much. Saitama wrapped his fingers around the cyborg’s member, moving his hand in time with their movements.

And when Genos came, it was a beautiful sight. All of that tension, all of that pressure released itself, broke. It was as if it was a jolt of electricity, a shockwave running down his body, his eyes widening, lips falling open, a shudder as he spilled into Saitama’s hand. That stunning masterpiece was enough to make Saitama follow, trembling through his own orgasm as he knotted within the omega.

That made Genos snap out of his daze, body suddenly alert as he ducked his head down and bit Saitama’s neck. To him, it was only a light pressure and it wouldn’t leave a mark but the sentiment was there. Their bond was created.

Genos straightened out and licked his lips, smiling when Saitama pulled him back down for a kiss, an easy and languid one that lacked the desperation of either of their heats.

“That was nice,” The alpha sighed when they separated. “We should do this more often.”

Genos chuckled, pressing his lips to Saitama’s temple. “I won’t say no.”

“Man, I’m hungry. Skipping both lunch and dinner was not a good idea.”

Genos moved to stand up. “Oh, I’ll—”

Hands at his hips stopped him abruptly. “We’re still attached. Please don’t rip my dick off.”



It would be much later, after both of their heats, that they discovered that unmated, unrelated people that spent a considerable amount of time together would eventually have their heats align. It was an uncommon occurrence due to the few numbers of unmated Alpha/Omega pairs that regularly spent time together and it was believed to be a natural, biological event that encouraged individuals to mate. When Genos relayed this information to Saitama, he laughed about it for 10 minutes, stating that even Mother Nature wanted them to bang.

Though, he had to admit that without her help, he wouldn’t be where he was now, head resting in Genos’ lap as they watched a cheesy romance movie.

He looked up at the omega, smiling at how he was so focused on the TV, its blue glow touching his pale face. His eyes were wide, luminous in the darkness. One of his hands was in Saitama’s, his other absently trailing fingers over the alpha’s shoulder. Saitama inhaled deeply, enjoying the gentle smell of oranges as he shifted against his mate. And Genos took in one of his own, sighing as lavender touched his nose.