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Luffy gets home early and is met with a wave of musk the second the door opens. A wrinkle of his nose only brings the scent stronger, the weight of pheromones heavy on the roof of his mouth.
He knew Ace was staying home today since his rut was close and Ace’s work had given him the appropriate rut-leave. Sabo fussed over the other alpha before he left for work and had gotten himself aggressively scent marked for it.
Luffy smiles when he remembers how Sabo had complained and ran back into the bathroom to fix his hair after Ace had left a huge, wet stripe of spit along the side of his face which messed his hair up.
“Ace? Are you okay?” Luffy calls into the hallway after slinging his bag by the door, shoes kicked off quickly.
There’s no answer.
Luffy trails down the hallway while pulling his uniform off. The stupid button up is so stuffy all the time and Ace has mentioned to him before that he hates when Luffy comes home and brings the scent of his entire school with him on his clothes. Sabo has gotten similar complaints from Ace, who is such a stickler and sensitive to outside scents on his brothers.
Debating if he should take a shower or not, Luffy slows down as he gets closer to the door at the end of the hall, Ace’s room. It’s closed all the way and there’s no light on under it. Luffy is starting to doubt if Ace is even home right now with how quiet it is, and if he is, he must be asleep since he didn’t answer the first time…
Thinking better of it, Luffy takes a quick shower just to rinse off and scrub himself twice over with Ace’s bodywash, remembering Sabo’s mild scolding from the past, “don’t agitate Ace anymore than he needs to be when he’s in rut. Ace gets really sensitive to everything. He needs to be left alone. Rut’s aren’t fun.”
Remembering how miserable he gets during his heats, Luffy understands that he should be a little more considerate of Ace right now. He’ll do his best to think about things before he does them, since that’s always Ace and Sabo’s biggest scolding remark. Think before you do something, dumbass.
What Luffy isn’t expecting is to open the bathroom door, only wrapped up in a towel slung around his waist and water still dripping off his hair and down his back, to find Ace standing in his doorway in the dark at the end of the hall.
Luffy startles, just slightly because he doesn’t notice Ace is there until the alpha growls.
“Ace! Holy crap, you scared me. Did you… just wake up?”
There’s silence, but Ace’s head turns, piercing eyes on Luffy as soon as he starts talking.
Only after Luffy clocks the way Ace’s dark, almost black eyes fully put together Luffy’s nudity, that the omega catches the overwhelming scent of pheromones that fall from Ace’s room in a wave.
It’s heavy, a warm musk that clings to the roof of Luffy’s mouth. One of those odd smells that he can just barely catch a taste of on his tongue. It’s very Ace. A burnt note to it, smokey, aggressive and full.
Swallowing, Luffy holds very still, ignoring the way goosebumps raise on his arms and neck. His instincts are flaring, responding to an alpha in rut so close. The clenching low in his belly means that heat pools right between his legs, and Luffy is suddenly hyper aware of being completely naked.
“A-Ace…? Are you okay?”
More of that heavy silence.
Staring.
Luffy’s skin prickles again as something rabbit quick jumps up from his belly right into his throat. It whines, danger! Danger! You’re in trouble! Get away. Get away get away!
He’s so stupid, he knows he’s stupid, but he doesn’t think about it when he turns on his heel and runs.
Ace looks dangerous. A dark, huffing silhouette of his bulky frame at the end of the hall. The only light illuminating him from a dim lamp in his room at his back.
Luffy has seen that piercing look in Ace’s eyes only a few times, when he’s about to snap his teeth at someone, when his fists get clenched tight with blood on his knuckles, when his alpha instincts flare up.
Suddenly, Luffy remembers how predators go for the throat when catching something small.
He doesn’t mean to run. He knows better, but Ace scares him in that split second that he notices a muscle in Ace’s shoulders jump. He doesn’t see anything else before he thuds for the living room. It’s open there, safer. He can grab his phone that is still in his schoolbag and call for Sabo. Because he’ll know what to do, how to handle Ace.
Luffy hasn’t ever seen Ace when he’s in a rut before. He’s only ever seen him agitated and snippy and snarling right before a rut, and the oppressive, clingy big-bear grumpiness that comes after a rut, where he stinks up the whole apartment and demands more hugs without ever asking for them, just tugging him or Sabo into his lap or his side before he smothers them in his scent.
It’s useless, Luffy doesn’t even get close to his bag. A heavy, solid weight barrels into him from behind and he topples to the floor with a yelp. There’s a low, chest rattling growl that comes from Ace, and it practically vibrates Luffy from the inside out.
“Omega.”
Scared, heart racing, and towel slipping off his bare hips, Luffy yells out as he throws an elbow back. He can feel hot breath on his skin, a wet, slimy drip of drool that hits his neck before his elbow connects with Ace’s jaw. They tumble away from each other, a mess of limbs as Luffy rolls over onto his back to try and scoot away, barely missing the fingers that grab for his leg blindly.
He’s on his feet in the next hurried breath of air in his lungs. He gets a second to actually see Ace and that he’s naked too, skin flushed and sweat slick all over, muscles bulging under his tan skin. His fangs are dropped and scary big. They’re proper alpha fangs, made for claiming, maiming, biting, rending.
Ace’s cock is hard, standing right up and red all over, veins that map the shaft bulging, a glisten of wet all over the skin and glands and half swollen knot. There’s clear liquid at the tip of the flared head that drips to the living room carpet when the girth of his cock bobs and twitches on every step or noise Ace makes.
His eyes are pitch dark, pupils blown wide, but there’s a bright sort of clarity to them. He looks wild, and Luffy hasn’t ever seen Ace look at him like that before. Hasn’t seen him so big and snarling on every other breath, running only on instincts.
Luffy’s punch barely did anything apart from get Ace off him for two seconds. He has to hurry to his feet when Ace lunges for him again.
“Ace!? What– What are you doing?!”
Luffy darts quickly for the couch, hoping to put something big between the two of them. Ace is on his feet now, shoulders heaving, anger and hunger snarled onto his face. Luffy feels his knees shake, stomach clenching.
There’s a scent in the air that makes Luffy’s head dizzy. It smells good, makes him want to plant his feet and stop running. Maybe duck his head down. He can feel how his body reacts to the strange pheromones, tummy all squirmy hot and slick starting to wet the inside of his thighs.
The way his body pulses, practically begging to get closer to Ace and bury his nose into his neck, scares Luffy more than the crazy look his older brother is giving him right now.
“Ace, you’re scaring me… I don’t want to wrestle right now, please. I’m sorry I bothered you, I won't make any more noise, I promise,” Luffy shuffles to the side, glancing at his bag that is now on the other side of Ace. Blocked.
Ace doesn’t answer him, just like all the other times. Luffy would almost prefer to get cussed at just as long as it’s something from Ace that makes sense. Words. Something for him to work with.
The alpha only snarls in his direction again, slow on his feet as he stalks forward to round the couch on one side. Luffy carefully matches him, making sure the couch is a constant length between them. Ace goes to one side and Luffy stands at the other.
Despite the cold chill of the water drying on his skin, the dreaded fear that stays like ice on the back of his neck and in the pit of his stomach, Luffy forces his feet to keep moving. He doesn’t know what Ace will do if he catches him again.
They’ve circled the couch twice now and Luffy has finally managed to maneuver himself to have his back to the front door, bag behind him without Ace in his way. If he could just… have two seconds to run back and snatch it up, run to his room…
Ace rumbles again, a low, almost-growling noise in his chest. Enticing. Soothing, or at least an attempt to be.
“Come Here, Omega.”
Luffy’s foot slips forward, a jerk of momentum forward, to the other side of the couch where Ace is watching him, before he stops himself with a gasp.
Ace has never used his alpha voice on him before.
It feels like a betrayal, if he even had the shock left in him to feel it. He’s still trying to shake the Influence off himself, the way the command still echoes like a whisper in his head. Go to Alpha, it tells him. Alpha called you, it seethes. Go to him. Go to him. Go to him.
Luffy doesn’t realize he’s at the end of the couch until he’s blinking and suddenly Ace is right there in front of him, viper quick and snatching him up by the arm. Luffy screams, shocked at himself for still obeying even after he fought it off initially and the flash of fear.
There’s heat against his hip, a heavy, thick weight that smears wet on him before he realizes that it’s Ace’s cock. Luffy gets shoved unceremoniously over the rounded arm of the couch, and the heft of Ace’s cock slots between his ass instead now.
“No!” He squirms, thrashing in the hold even as Ace’s hands battle away his arms and keep shoving his shoulders down. It’s useless.
“No! No, no, no, Ace no!” Luffy tries pushing up on his arms, bare feet kicking at Ace’s legs, to free himself from the crushing body that pins him into the couch. Luffy doesn’t even know what he’s fighting against, but he knows he shouldn’t let Ace catch him.
“Omega. Omega, behave.” Ace growls behind him again in warning and Luffy wheezes at the wall of pheromones that slam into him suddenly. A hand clamps down at the back of his neck and squeezes just as the rut pheromones flare up again stronger.
All of his muscles go slack, his omega turning belly up in his head. Luffy can hardly make a squeak when he’s crushed back down into the soft couch, cheek mashed into the cushions as Ace pins his weight onto the hold he has of Luffy’s nape.
“Gonna breed, omega,” the alpha groans, “breed you full of my pups. Knot. Full of my cum. Breed you. Knot you.”
Tears spring into his eyes. Ace hardly sounds like himself, heavy, deep-chested grunts, low growls from his alpha that bares its fangs now like a threat.
“Don’t. Mhf- no, no, Ace, please don’t.”
Luffy whimpers when he feels Ace’s cock jerk up between his legs. His body is slicking without his permission now, responding to the alpha’s rut, the pheromones, the fear. He’s drenched his own thighs with it, an embarrassing amount that almost starts to drip to the floor if not for Ace’s cock catching it from the source now. Sliding through the wet until Ace’s entire length is soaked.
He humps between his legs like a dog, jerking, wild thrusts. Luffy bites down on another whimper when the flare of Ace’s knot bumps against his entrance. He can’t see it, but he can feel how the head of the alphas cock slips up between his legs and smears against his small omega cock.
The alpha’s hands are full, keeping a hold on the omega under him, pressing, claiming, holding tight so the little thing can’t run away from him. The thought of bringing a hand down to guide himself doesn’t even cross his rut-addled brain once. He shuffles on his feet and jerks his hips, trying to angle himself right to get the catch of Luffy’s wet hole and slam in.
Luffy tries to move, tries one last ditch at running away, but his arms lay limp over his head, halfway stretched out over the couch. Ace’s next thrust behind him shoves Luffy forward hard enough to knock his toes off the floor.
“Please. Ace, please,” a sniffle brings tears into his lashes and Luffy squeezes his eyes shut, “nii-chan.”
Ace only clamps harder down onto Luffy’s neck, thumb against the scent gland there hard enough to ache, hard enough that the pressure loosens Luffy’s hips, makes his legs go limp. Another thrust has Ace’s cock slipping between his thighs, a wet slap of their hips.
“Knot omega. Breed you with my pups. Knot, nngh, gonna–”
Between one frantic jerk of his hips and the next, his cockhead finally catches, a blunt, wet pressure that resists him at first before he snarls and breaks through. It’s a sudden tight, sucking wet heat, taking him in entirely until a vice grip squeezes just before his knot.
Luffy screeches, eyes rolling back as heat flares up in his belly. He can’t even rise up on his toes, hooked onto the alpha’s cock so that his feet are clear off the carpet now. The full stretch barely hurts, small body already wet and ready for the alpha.
Nononono, we can’t– we can’t, his mouth doesn’t work, his lungs empty, unable to form the words with his lips, unable to breathe the protest onto a whisper.
Orgasm takes over his body like a sharp yank of a hook in his guts. He’s not aware of it, just finds himself floating and dizzy and numb all of a sudden. Luffy comes back to himself in slow, hard jolts, not realizing that it’s the alpha fucking him until he can actually feel his own skin again.
It feels good. Oh, it feels so good. Better than anything Luffy has ever felt before. His entire body aches, his throat feels raw, his hips are numb, but the stretch, the scent of the alpha behind him, the hot bulge of the knot that catches at his hole on every thrust is too much for him to take.
Ace is fucking him in hard, frantic thrusts. He doesn’t have to fight the little omega anymore, sweet thing gone limp and submissive for him. His alpha purrs under his skin, pushing at his bones and making his gums ache with the satisfaction. But the want is still there. He wants. He needs.
He’ll breed the omega until he’s round and fat with a litter. He’ll knot the sweet, small omega and keep him there on his knot even after it’s locked them together for days. He’ll drag Luffy back into his den, spread his legs and make sure his womb is never left empty again.
The couch under them creaks dangerously. The wood frame from the inside now taking the brunt of the force from his thrusts. Ace doesn’t pay the noise any attention once he has determined it isn’t the front door opening.
Each thrust now knocks the couch forward, barely a half inch at a time. Ace holds Luffy’s hips tight, fingers bruising, adjusting his grip with both hands to the small, lithe waist. It’s the couch that’s moving, not Luffy, but his instincts take it as a threat. Omega is running away, trying to get off his cock.
He steps forward to go after him, not that Luffy is moving very far regardless, but Ace can’t keep his feet planted and fuck in as deep as before. He steps into the distance, closing it, growls in pleasure when the blunt head of his cock knocks into the omega’s cervix again and again and again.
Keening whines bubble up from under him, choked off little things that barely register to his ears. Omega feels good, that’s all his alpha cares about now. Omega’s body is open and fertile and ready for his seed.
The wet, clenching hole around his cock isn’t going anywhere now, and Ace braces his hands onto the cushions on either side of Luffy’s shoulders. His fangs ache, wanting to lean over and get at the back of the pale, thin neck. The angle is all wrong for it though, and he’s not able to reach even when he leans all the way in.
Luffy whines at the feeling of breath on his nape though, shoulders hunching. He keeps his arms crossed over the top of his head, fingers pulling at the edge of the couch cushion every time Ace’s cock drives into him knot deep.
Drool soaks into the couch under his open mouth, almost as messy as the wet, soaking mess between his legs. Each deep press of Ace’s cock comes with a filthy squelch, slick gushing out of him in strings that get flung to the floor as the alpha’s heavy balls connect with his hole.
Luffy can’t keep track of how many times he’s cum already. His cunt feels raw, numb, split open and nothing more than a wet, hot gash for Ace to use for his rut. The couch has run into the wall now, and Luffy barely clings to the cushions with shaking hands, trying to keep his arms straight so he can push his body back to meet Ace’s rutting.
The couch rubs his trapped cock raw, pinned by his own hips and soaking the arm of the couch with pre and slick and cum. He can’t stop crying, all of a sudden, presenting himself trapped by his older brother against the couch, whining and gasping and begging for the alpha’s knot.
It’s swelling already. Stretching him to his limits. Ace is fucking it into him little by little, splitting him open on his knot that throbs and swells more and more every time he yanks it from Luffy’s wet little hole with a pop.
The drawbacks are excruciating, Luffy’s got his teeth in the couch now, trying to bite down the keening, needy sounds that work their way up his throat without meaning to. His stomach keeps cramping, thighs shaking, toes curling. His body begs for the knot to catch and lock inside of him. Every time Ace pulls it out it feels like torture.
A plea is on the tip of his tongue and he’s about to come to terms with throwing all sense of reason out of his head and just begging his brother to fucking knot him already and stop teasing. But Ace of course beats him to it.
The alpha’s grip adjusts, burning hot hands finding the trim pinch of his waist, just under his ribs and grabbing hold, pulling Luffy into his hips as he makes one final, slow roll of his hips forward. The swollen knot breaks the stretch of his hole, squeezing in with a final, slick pop.
When he tries to pull back, his knot catches, flared and swollen too big to pull free now. Luffy gasps, scrambling at the couch cushions for some sort of reprieve, comfort, anything.
Just the pull of the locked in knot makes his back arch, climax squeezing him all over like a death grip. He barely feels how his hole clamps down onto Ace’s cock, slick gushing out of him and splattering to the floor. His eyes roll back. It’s so good he can’t breathe, can’t even scream even though his lungs are burning for it.
His instincts are hissing, yes yes yes yes yesssss finally.
Smaller, shocking orgasms keep sparkling up his spine when Ace jerks his hips. The alpha behind him won’t hold still, whining as his knot flares and throbs and gets squeezed by Luffy’s walls. He can feel the cum rushing out of him, a steady, oozing gush of heat that fills him up.
Eventually, Luffy’s stomach starts to ache, too full, too warm, too much. He’s not even sure how long he’s been hanging off Ace’s knot for. Seconds? Minutes? An hour, by now, surely? His limbs are all still too weak to support himself. The arm of the couch is pressing into his swollen tummy.
Luffy tries to tell Ace it hurts, that he wants to roll over or move or at least beg the alpha to let his feet finally touch the ground again, but all that comes out is a gurgling, weak noise. One that Ace’s alpha responds to with a coo, wrists sliding up over Luffy’s ribs to rub aggressively and uncoordinated against the scent gland at his nape, then over his jaw, into his hairline.
The pheromones smother Luffy back down into his head, especially when Ace’s wrist smears a strong line of it across his cheek. He feels claimed and subdued, even without a bite to the neck. He falls limp against the couch again.
Awareness comes back to Luffy in a slow fog, a haze that brightens the back of his mind. There’s fingers in his hair, petting him until all of his sweaty curls are off his neck and ears and face. Luffy doesn’t want to open his eyes yet, scared he’ll see that wild, dark look in Ace’s eyes again.
“Omega…”
He doesn’t answer. Keeps his head down, the back of his neck bared for the alpha, still stuck on his knot and unable to run off.
The hands in his hair smooth over his head again, almost like a ruffle. A thumb slips across his cheek.
“Luffy.”
He opens his eyes finally, looking back, hoping the clarity in Ace’s voice will mean he’s normal again, even though he knows it was much too short for Ace’s rut to be over with.
There’s a faint, gold ring around Ace’s irises, the glow of his alpha. Luffy’s only seen his eyes like this twice, when he’s lost control of his instincts.
“Take care of you,” Ace says, carefully, slow, like he’s mulling over every stilted word. Like he’s struggling to keep himself lucid.
Luffy doesn’t even have time to question what Ace means before he’s dragged backwards by the knot inside of him and hands bruising on his hips. The omega yips, pain-pleasure seizing his lower back, legs numb, head heavy.
Limp as he is, Ace still doesn’t have trouble picking Luffy up, bracing him with his arms as he steps away from the couch. Luffy feels weightless and is scared for the moment he gets dropped. He’ll go right to the floor, he knows it. His legs feel like mush.
Instead, Ace carries him all the way back into his room, despite Luffy’s weak pawing at his arms. His feet barely come close to the floor. It’s embarrassing, the way Luffy’s cock leaks and drips down his thighs with every step the alpha makes, jostling the swollen knot and hard cock still inside of him.
He’s all of a sudden enveloped by Ace’s scent, warm and smokey. There’s a bunch of blankets and clothes on Ace’s bed, one of Sabo’s pillows, a few of Luffy’s shirts. Those scents are barely perceptible under the whole of Ace’s rut pheromones.
“Ace. I can’t be in your den when you’re in rut, Sabo said…”
Luffy whines. Sabo told him he should stay away from Ace’s room altogether when he was in rut. And now he’s done the one thing he was told not to do. He doesn’t want to get in trouble, doesn’t want Sabo lecturing him, and he doesn’t want to make Ace’s rut any more unbearable than it is.
But Ace doesn’t let him move away. He’s still knot deep inside of him, and Ace curls himself behind Luffy and squeezes him into his arms, a hand rubbing the small swell of Luffy’s belly.
“Gonna breed omega.”
Luffy feels the rumbling purr in the alpha’s chest, right up against his back.
“But– eeh–!” Luffy squirms at the sudden warm lick of a tongue up the side of his neck. Ace does it again, groaning into Luffy’s ear now when he licks over the shell of it, wet and slimy.
Luffy’s body tenses, trembling at the way the lick makes him feel good. He can feel himself slicking, skin flushing warm all over, nerves tingling.
The knot inside of him throbs again, another strong pulse of cum shooting into his cunt, pressed deep. Ace licks him again, finding that Luffy’s ears were weak to the pleasure, that the omega would clench around him every time he did it.
He goes slow, placated with his alpha finally able to cum, filling up the smaller body under him. Breeding him. His alpha rumbles in his chest again, the retting craze less intense in his brain now thanks to the squeeze around his knot. It’s the first time he’s had a rut where cumming doesn’t make him hurt more.
He’ll keep Luffy here, keep the small, fertile omega trapped on his knot for the rest of the day, plug him full until he was rank with the scent of alpha. Everyone would know who Luffy belonged to, would know immediately that he was carrying pups.
The slow, easy rut of his hips keeps friction on his cock. He doesn’t pull away enough for it to hurt, just enough to hump into the omega and keep his walls clutching at his knot, milking him for every last drop of his seed.
The lazy, grinding rutting and licking finally makes Luffy break. It’s the most intense orgasm he’s had yet, building in his hips slowly, an inevitable all-consuming pressure that makes him pant and squirm. It comes slow enough that he knows it’s coming, knows that it’ll be intense and he can do nothing to escape it.
Ace must feel it too and the alpha presses his hand on Luffy’s belly, like if he presses hard enough he could feel the moment Luffy got pregnant under his hand. His other slips up to Luffy’s chest, keeping his back arched.
Ace’s strong fingers take him under the jaw, pulling his head back, exposing his neck. Hyperventilating, Luffy scrambles at the blankets, the sheets, Ace’s arms. Cumming hasn’t ever felt like this, wave after wave of pleasure beating him down.
Ace’s mouth latches onto the small scent gland under the hinge of Luffy’s jaw, wet lips, soft tongue, suckling pressure with a tease of teeth. Luffy’s nails claw into Ace’s arm, scoring pink lines into the tan skin as he sobs.
“Nnnngh– Ace–”
Ace keeps grinding into him, even as the orgasm bleeds out of him. Keeps grinding and rolling his hips in slow, easy ruts until Luffy’s cum dribbles from his cock in small pulses, gone dry until warmth takes its place.
Luffy finds himself crying against the pleasure of it, the release of his bladder, the growing warm against his thigh as he pisses himself. It’s humiliating, trapped in Ace’s arms as he wets the bed, still trembling from the best orgasm of his fucking life.
Ace is purring though, the alpha’s low tone almost a growl in his chest. His cheek nuzzles against Luffy’s, smothering him in his scent. Luffy feels his ears ringing hotly, staring down at himself through the haze of tears, watching the stream of his own urine turn into a trickle, the last few spurts forced out of him as the alpha’s cock keeps grinding into him.
“No more,” he blubbers, hiccupping as Ace’s arms tighten around him, “Ace. Please, I can’t- I can’t anymore.”
“Mmm. Have breed you full, omega,” Ace says again, satisfaction oozing off him in waves. Luffy can smell it on him, the way his alpha is so happy and proud of himself.
Luffy gasps when Ace pushes him forward, rolling them until Luffy is spread out onto his front, hips soaking wet from the puddle of slick and cum and piss that’s under him now. Ace crushes him down into his den with his bodyweight.
Dread fills him, when Luffy catches sight of Ace’s clock on his nightstand. He’s going to die. Oh. Oh, he won’t make it. There’s hours before Sabo comes home from work. Luffy whimpers to himself, hoping that Ace gets tired between this swell of his knot and the next.