SUMMARY: Any good little brother would do anything for their older brother. And Ritsu is a very good little brother.
AO3 TAGS: Alternate Universe, Alternate Universe - Canon Divergence, Omega Verse, Alpha/Omega, Alpha/Beta/Omega Dynamics, Alpha Kageyama Ritsu, Omega Kageyama "Mob" Shigeo, Possessive Kageyama Ritsu, Pre-Awakening, Non-Powered Kageyama Ritsu, Underage Kageyama Ritsu, Underage Kageyama "Mob" Shigeo, Incest, Sibling Incest, Brother/Brother Incest, Underage Sex, Consensual Underage Sex, Top Kageyama Ritsu, Bottom Kageyama "Mob" Shigeo, Anal, Anal Sex, Knotting, Established Relationship, Plot What Plot/Porn Without Plot
AN: *watches Voltron*
*starts Voltron fic*
*watches Naruto*
*stops writing Voltron fic to start Naruto fic*
*watches MP100*
*stops writing Naruto fic to write MP100 fic*
someone save my WIPs from me
I never go into a new fandom looking to ship something, and yet, here I am. I can't even remember what it was, I just remember Ritsu doing or saying something and I was slapped with the need for possessive Ritsu… help…
EDIT: Original summary was moved to the c1 Summary when I added a second chapter to make way for an overall fic-themed summary.
CHATPER SUMMARY: "I dreamed that I'd taken a different route home today," Ritsu confessed, trying to remain calm, trying to keep the roll of hips, the glide of his cock in and out of his brother, smooth and even. He could still see those alpha's faces in his mind, could still remember the way his omega has smelled, wrapped in their faint scents. "That I never saw you with those alphas, that they took you away and had their way with you. That they took you from me."
CHAPTER 1 - NIGHTMARE
"Aren't you an adorable omega?"
"Maybe you can help us find someone, cutie."
"Maybe we can make it with your while…"
It was easy to find the source of the catcalls - almost every person in the plaza was moving towards their destination except for a small group of boys wearing Miso Middle School uniforms standing in a half circle. Ritsu suppressed a sigh of annoyance and moved towards them to make sure the omega didn't need any help.
"Yeah, have you heard of White T Poison? We know he goes to Salt-"
There was a suspicious sinking feeling in Ritsu's belly and he started to jog, nose lifted into the air, trying to catch the scent that he just knew was going to be there. He circled around the outside of the boys - there was only four of them - and found an opening. An opening where Mob's familiar form was standing, head tilted back to look the taller alphas in their faces.
All four boys were leaning too far into Mob's space, their scents unchecked in the air, clinging to Ritsu's brother. And Mob was just standing there, posture, face, and scent relaxed, no hint of rejection or even challenge. For all that Mob was the most powerful person Ritsu knew, possibly the most powerful person ever, he was also the person least likely to use that power, especially on another person. And yet, it was as if every evolutionary instinct bred into omegas had just skipped his older brother entirely - Mob wouldn't protect himself if his life counted on it. That was alright - that's what Mob had Ritsu for.
"Why don't you come with us and we'll show you what White T Poison did? A little demonstration? Maybe that'll help you help us."
Mob - gentle, innocent, naive Mob - nodded his head as he stepped forward. "Okay."
Possessive fury ripped through Ritsu and he clenched his jaw tight, trying to keep it inside as he stepped up behind his brother, stopping his forward momentum with an arm around his shoulders and across his chest. "Nii-san."
"Ah," Mob murmured in his own soft brand of surprise. "Ritsu."
Something in his scent, something small, almost imperceptible, even to Ritsu, who had spent his whole life with Mob, shifted as Mob relaxed back into Ritsu's chest. The furl of fury in Ritsu's chest loosened at his brother's easy acceptance of his claim and he let his scent wrap around his brother, banishing the weak scent-claims of the strange alphas.
Ritsu turned his glare on them, holding Mob tighter. "What did you need from my nii-san?"
If they really wanted Mob, they could have fought Ritsu for him, but the only thing worse than trying to fight a mated alpha was trying to fight a familial alpha. Mob may have had to look up a handful of centimeters to be able to make eye contact with the alphas, but Ritsu could stare them down head-on, and though they might have had more experience, and more fighters, than Ritsu, it was clear none of them wanted to pick a fight in a physical space. Especially not over a single omega.
One of the alphas, the one who had been closest to Mob, the one who'd been the closest to touching Mob, bit out a "Tch-" and leaned back, and the other three followed suit. "Nevermind," he nearly growled before turning sharply and striding away. His friends looked after him, looked at Ritsu, then back to their leader before scampering to follow.
It only took a minute before they were out of sight, taking their disgruntled pheromone trails with them, and it was only then that Ritsu relaxed, pulling away to step up aside his brother. He left his arm across Mob's back, his hand on Mob's shoulder, a claiming touch, and smiled down at Mob.
"Alright, Nii-san?" he asked, smiling gently.
Mob smiled back, a small, soft little thing that was only for Ritsu, a tiny shift of facial muscles but enough to make that possession curl into a black little ball in Ritsu's heart. "Yes, thank you, Ritsu." He looked away towards the alphas. "I hope they find who they were looking for."
Ritsu blinked, and then he laughed. Powerful, naive Mob. Beloved, unselfish Nii-san. "Let's go home."
Ritsu bolted upright, panting hard into the silence of his bedroom. The sudden departure from his dreams left him disoriented, and it took a few moments to realize he was growling, his teeth sharp in his lip, his pheromones out of control in the small room. He forced himself to breathe steady, to calm his heart and bring his scent back under control, but even as the clock on his nightstand ticked closer to morning, he couldn't quite shake the emotions that had force him awake.
He paused outside of his parent's room, listening hard, before creeping across the hall to Mob's room, the door opening silently under his hand. "Nii-san? You awake?" he whispered into the dark. There was no response, and after a few moments, his eyes adjusted to the pale moonlight barely illuminating the room.
Mob's futon was slightly off to the side, his brother's body a nearly-indistinguishable lump of blankets. Ritsu had never understood why his brother had rejected a more western bed like he and their parents had, and he'd always wondered if it was another manifestation of his brother's almost-unreasonable unselfishness. Mob didn't stir until Ritsu was sliding under the covers, pressing up tight against his older brother's smaller back.
"Ritsu?" The soft sound was a sleepy slur, the turn of Mob's head even sleepier, nose brushing along the line of Ritsu's jaw, a sweet, barely awake scenting. "Sfrbl… 'ay?"
"Nightmare, nii-san," Ritsu whispered back, pressing a smile into the side of Mob's neck.
His older brother hummed and tilted his head away, exposing more of his neck for Ritsu, inviting the gentle scrape of teeth. Ritsu shushed him even as he wrapped an arm around Mob's waist and slid his hand into Mob's sleep pants. His omega's cock was already hardening, and endulated into the easy, exploratory pressure of his fingers. He indulged only for a few moments, stroking Mob to hardness, before he slowly pulled his hand back and began to push at Mob's pants. The omega lifted his hips, sleep-numbed hands almost hindering the progress Ritsu was making rather than assisting, but finally Mob's pants were around his knees.
The blanket shifted when Ritsu pushed his own pants down, and the sweet scent of omega arousal drifted out to his nose, making his cock throb. Sometimes Ritsu wondered if it was some part of his brother's psychic powers affecting his scent, or if that's how he would smell even if he'd been born powerless. There was none of heady, saccharine lure as was common in omegas prone to domesticity, nor was there the spicy, mouth-watering temptation of adventure-driven omegas. No, Mob had to be different there too - his scent wasn't exactly a scent, but rather something akin to what Ritsu thought a cat laying on fresh laundry in the sun might feel like.
Ritsu pressed his fingers into where Mob was already wet, more so that he could immediately put them against his tongue and lick them free of slick than to test if Mob was loose enough - he was always loose enough, he was always ready to take Ritsu when Ritsu needed to take him. The second time he pushed his fingers into his brother's welcome heat, he had to force himself not to put them back in his mouth, but to use them to slick his cock.
Mob's body opened around him, pulling him in, and Ritsu carefully pressed his teeth to his brother's neck, careful not to break skin and careful not to make a sound. He never had to worry about Mob making a sound, his brother was as quiet in sex as he was in life, but there was a feeling in the air like lightning about to strike. After Ritsu fell still with his hips pressed to Mob's ass, the barely-yet-there swelling of his knot wrapped tight in slick heat, he smoothed his damp hand up his brother's chest to gently grip Mob's jaw and turn his mouth into Ritsu's. The kiss was forcibly soft and gentle, carefully done to calm Mob's heart and his mood, to sieve the sensation of lightning from the air.
Ritsu had only seen his brother loose control once, and it had terrified him - not because he feared for himself, but because he feared for his brother. At that time, it had been in his defense, and he'd been protected and safe, both from the older boys and his brother, but he wasn't sure that who, or what, had saved him had been his Mob. Ritsu had always done what he could to keep his beloved nii-san happy, but he'd always been extra careful after that, petrified that that other being would replace Mob and he'd lose who he loved most. There was no telling if Mob would break in that same way if he lost control while Ritsu was inside of him, so as always, Ritsu would protect his brother when he couldn't protect himself.
"What- what was your nightmare about, Ritsu?" Mob rasped against Ritsu's lips, eyes half-lidded and body relaxed in Ritsu's embrace and around his cock.
Ritsu pressed a last chaste kiss to Mob's cheek before reaching down to hook his fingers behind the knee of Mob's top leg, pulling it up the futon, forcing Mob more onto his chest and opening him further. Mob's eyes fluttered, and then closed entirely when Ritsu, leaning into the warmth of his older brother and balanced on his elbow, rocked out and back in. The sensation sent heat through Ritsu's groin and up his spine, and he had to lean down to press his face to his brother's neck again, breathe right into where mating mark was supposed to go. Where Ritsu's mark could never be, but it was a daydream that he returned to time and time again, regardless. Some days, it was all Ritsu could do to push down the burning desire to sink his teeth in the delicate skin at the back of his brother's neck and fuck the consequences.
"I dreamed that I'd taken a different route home today," Ritsu confessed, trying to remain calm, trying to keep the roll of hips, the glide of his cock in and out of his brother, smooth and even. He could still see those alpha's faces in his mind, could still remember the way his omega has smelled, wrapped in their faint scents. "That I never saw you with those alphas, that they took you away and had their way with you. That they took you from me."
Despite his efforts, rage filled him and the air again, made his steady rhythm falter when he jerked forward a little too hard, made his teeth a little too sharp. Mob's breath hitched, his body paused a moment almost too long, and then he lifted his hips into Ritsu's harsher rhythm. Ritsu's knot was slowly expanding as the heat in his groin grew, but Mob's body easily took it under the force of his sharp thrusts. Ritsu had to turn his head into his brother's pillow to breathe in the ingrained scent, and keep himself from biting into the back of Mob's neck, his breaths exaggeratedly steady until his hips stilled.
"Ritsu," Mob whispered, voice wavering, and it was that waver that helped Ritsu pull himself together.
Ever since his brother had closed himself off from his own emotions, ever since he had affectated the blank state he now lived in, the tiniest little thing could be an indicator of his mood. Most rarely it was a shift in that soft, comforting scent, sometimes it was a tension in Mob's voice or body, but usually it was the smallest hint of an expression, pulling at unused facial muscles. Now, as Ritsu renewed his control on himself, he could see the tension at the corners of his nii-san's eyes and the slight wobble to his lips, could feel the tremor in the smaller body under his, could scent the faint call of need in the air. He had to calm down and focus, for Mob, if not himself.
"Sorry," he murmured, leaning over Mob to nuzzle gently at his jawline. He let the sweet but faint scent of omega arousal relax him until he was half laying on his brother, cock hard but still in the pulsing heat. "I'm sorry, nii-san. Didn't mean to lose control. I just can't stand the thought of you being taken from me."
His omega's cock was small but hard, and Ritus carefully, gently cupped it in his hand, pressing it to his brother's belly. Leaning up on his elbow over Mob, Ritsu had the perfect view to see when Mob's eyes fluttered at his touch, to see when his chest froze and then juddered as his brother fought for self control. When Ritsu pulled out and then pushed back in, stroking down Mob's cock, Mob's eyes fell closed, his eyelashes like shadows. He pressed a soft kiss to Mob's temple as he fell into the steady rhythm, careful not to let his emotions disrupt the beat. Even the wet sounds of his cock pushing in and pulling out of his brother were muted.
"I-" Mob started and then stopped, mouth opening and closing as he tried to find his words. Ritsu nuzzled at his hairline in silent encouragement. "I will always be here for you, Ritsu."
Hunger flashed through Ritsu, sharp and hot, and he had to swallow hard against the sudden influx of saliva in his mouth. His teeth almost ached with the need to sink into flesh, and his heart echoed the desire to bond them. His knot was starting to throb, his balls drawing up tight."I know, nii-san. I hope you never forget the reverse is also true."
At that, the corner of Mob's mouth twitched, a phantom of that smile-just-for-Ritsu. "I know."
It was that small, almost-smile that did it, that sent that heat in his spine rushing through and out him. Ritsu carefully set his teeth to the cloth-covered curve of Mob's shoulder as he firmly and steadily forced his knot into his brother, breathing out as he came and expanded into the come-soaked heat. Under the unyielding press of his hips against Mob's ass, the force of his knot against Mob's prostate, and the curve of his fingers around Mob's cock, his omega started to come too.
Something in the air broke, a tension Ritsu hadn't even noticed had been building, as wet spilled into Ritsu's hand and the muscles around his cock started to spasm, milking him of seed that would find no home, if only because his older brother was so careful with his birth control. He could even feel the beat of Mob's heart around his cock, and his own was a thumping echo he could feel through his whole body.
The pleasure, as always, was slow to fade, even if it was only because his swollen knot tied them together, keeping him inside that delicious burning heat and sending frissions of lava up his spine if he did more than simply breathe. The air was saturated with the scent of their sex, and even though he'd just come, it effortlessly reignited Ritsu's hunger for his omega, made him throb inside of Mob. Mob shifted with a soft sound, one too soft for Ritsu to decipher, and Ritsu finally lifted his cupped hand from the soft cock, bringing it to his mouth to lick clean.
"Ritsu…" Mob sighed into the quiet room. His body was as it always was, soft and pliant against Ritsu's, but after Ritsu knotted him, he was always just a little more boneless, a little more malleable.
"Yes, nii-san?" he whispered back, mouth filled with his brother's taste - it wasn't as addictive as the taste of Mob's slick, but it still helped eased his near-insatiable and unending craving.
Mob was silent for too long, long enough for Ritsu to be satisfied that he'd lapped it all up before wrapping an arm around Mob's waist. He curled up tight around his brother, half wondering if Mob was always going to be shorter than him. The shift sent muscles rippling around his sensitive cock, and for a moment, Ritsu's hold went a little too tight, until a gentle hand stroking his fingers helped him relax. Mob still hadn't answered.
"Are you alright, nii-san?" he asked worriedly, sliding his hand up Mob's chest to press against his heart. He could still feel Mob's steady heart rate against his cock, but he'd found that the touch helped to ground his brother.
"Mm," Mob finally hummed with a small nod. "I was just wondering…"
He trailed off again and Ritsu suppressed a sigh. Even if his brother was bleeding out, he would hesitate to ask for help.
"Ask me anything, nii-san," Ritsu encouraged, emphasizing the sentiment with a soft, reassuring growl.
"My next heat is during okaa-san and otou-san's vacation."
It wasn't so much a question as a reminder, but Ritsu heard the supplication as if it had been shouted at him. He forced his lungs to continue at a steady pace, forced his body not to curl tight like a cage around his brother, forced the alpha side of himself - the side that wanted to claw and bite and mark - into submission, and pressed a soft kiss to the curve of his omega's neck. Mob, tempting fate, sighed softly and trembled in Ritsu's arm, back arching into Ritsu's chest, ass gripping Ritsu's cock so tight it was as if Mob would never let go.
"Don't worry, nii-san," Ritsu whispered, mind aflame with the memory of the last time he'd satisfied Mob's heat, so long ago. Too long ago. The knowledge that his brother wanted him for his next heat would haunt him for the next several weeks, would keep him distracted during student council meetings and keep him awake at night. It was going to be well worth it. "I'll take care of you."
FIN
"I probably won't be writing any more for this ship/fandom," she says, knowing full well that she can never plan for such things.
Btw, if you haven't seen liieyn (on tumblr)'s RitsuMob art, you're missing out - it's so soft~
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