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The Butt You Rut™

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Derek has been increasingly restless around the pack lately. He hasn't reverted to the moody fucking asshole Alpha he used to be, it's more like he's... well. Like Stiles' ADHD suddenly became contagious. Stiles is honestly thinking about offering Derek some of his Adderall before he goes running into traffic after a squirrel or something. And though Stiles had noticed Derek's odd behavior ramping up in the last month or so, he's still left completely stunned when it happens.

It's just after a pack meeting and Stiles is on clean-up duty in the pack's chore rotation. Everything's gone quiet around him, and he's humming to himself, kind of bopping along to the music in his head as he scrapes and rinses. He bends over to put a plate in the dishwasher when suddenly, Derek is right there, ,grabbing him by the hips and well... humping his ass crack.

It's completely hot, to be honest. But for a very brief second Stiles panics, thinking he's managed to slip into a porny day dream about Derek again. His vivid memories of the teasing that had ensued from the rest of the pack in the wake of the last time that happened don't work to snap him out of the daydream though which clues him in to the fact that it's not. A daydream, that is. But he's still caught up in the grinding and the loud, almost whining panting noises that are ringing off the kitchen tiles. They're filling his head with thoughts and his body with want.

He closes his eyes, one hand braced against the granite countertop, the other still gripping the dirty plate — he can feel his thumb smearing through the cool spaghetti sauce that didn't come off when he scraped it — and gasps when Derek hitches his hips higher, lifting his feet completely off the ground to grind filthily against him.

The movement has Stiles' eyes flying open, and he's staring down at a knife that some jackass tossed in the silverware basket blade side up. If his hand slips...


Quick as a blink, Derek's gone, dropping him like he's hot, and Stiles has to do some nifty gymnastics to avoid impaling himself on sharp objects. From where he lands on his ass on the floor, Stiles looks up, still shaken from the knife to the face accident that had almost happened — and wouldn't that be fun to explain to his dad — and still completely aroused-bewildered at the whole last ninety seconds of his life.

It's almost sad how often he feels the conflicting sensations of arousal and fear that it's only the bewilderment that has him thrown for a loop.

"What—" is all Derek lets him get out before he's muttering something that sounds apologetic but is really not quite a word. He crinkle curls his eyebrows at Stiles, his mouth sort of flat and woeful, and his foot is inching backward to make an escape.

Uh. No. Abso-fucking-lutely not.

"Stop right there." Stiles' voice is firm and sharp — he took a K9 training course over the summer and wow, would his instructors be proud of him now. "Stop," Stiles repeats, scrambling to his feet, one hand making a halt gesture at Derek.

He moves quickly, grabbing Derek's arm and hauling him bodily into the living area of the loft, kicking the back of Derek's knee so he falls to the cushions. Keeping his hand clamped on Derek's arm, he turns bodily toward Derek and says, "In the past week, have you made contact with, been in the vicinity of, or pissed off a: darach, witch, pixie, warlock, shaman, druid, or other magical creature not specifically named but which we can hopefully still find some record of in the bestiary?"

Derek is sitting stiff as a board, his legs pressed together at a right angle to his torso. His body language screams discomfort, but Stiles can't let that sway him. Not when Derek's safety and that of the entire pack might be at risk.

Stiles nudges him with an elbow and a shaky gasp bursts from Derek. "No!" Derek's face does a squishy thing at the volume of his own voice and he addresses a softer apology to his knees. "It's not a curse or a spell gone wrong. It's... I know what it is, I just thought I had it..." He trails off, eyes going a little wide and panicky.

"Okay, well." Stiles drops his hand from Derek's arm now that the threat of impending escape seems over. "Is it, umm. Is it me?" He tries, he really does, but his own internal hope floods his words, and probably his scent.

Derek tilts his head, like he's listening to a police siren in the distance. "No," he finally says. "I don't think so."

And if Stiles deflates like a balloon improperly tied off, well. Who can blame him? It's a little crushing, especially since his ass is still buzzing from the really lovely grinding it received.

"Huh. Well, what is it? Because, buddy, let me tell you. I'm glad you know what's wrong with you and that you think you've taken measures to correct it. But. I've met you and your plans, okay. And I'm pretty sure even you would agree that mine are always better." Stiles politely pretends to ignore the way Derek's eyes roll because he knows they both know he's right.

"It's the wolf." Derek's back to muttering into his chest, but Stiles still picks it up, even with unenhanced hearing.


"When I gained the full shift—"

"When you digivolved—"

"I swear to god, I'll rip your throat out." But then Derek drops his furious gaze from Stiles' laughing eyes to his throat and his whole expression sort of looks like his brain maybe did a Blue Screen of Death, complete with open, drooling mouth.

Snapping his fingers in Derek's face brings him back to the present, and his ears light up a dull red at the tips. "What does your wolf have to do with this?" Stiles shifts again, feels the carpet-burny feeling in his ass, and sighs, drifting off himself for a second. "I mean, uh." He clears his throat. "I noticed you being weirder than usual a month or so ago, but you went all wolf on us more than a year ago."

"Yeah, well. It, uh." Derek coughs something that sounds like property into his fist and that makes no fucking sense.


"Puberty." Derek's frown is massive and frightening. "My wolf hit puberty and it..."

"Wants to hump everything it sees," Stiles finishes, his voice squeaky with stifled laughter.

Derek's sigh is deep and hard enough to ruffle the magazine someone abandoned on the coffee table. "Yeah."

Stiles waves his hand near Derek's face, knowing he needs to break Derek out of whatever mental pit he's falling into quickly even as Stiles is still fighting the urge to laugh. When Derek bares his teeth and bites the air near Stiles' offending fingers, Stiles just pulls them back and pretends to count them while grinning. "Computer," he finally says, his voice all haughty demand.

Derek's eyebrows do a funny dance before he points to his chest and says, "Nooo, I'm Derek," like he's talking to a particularly dim-witted child.

Stiles sighs, head flopping dramatically backward as he says, "I need your laptop, two hot pockets, and an unlimited supply of Red Bull if you expect me to figure out what's going on with you."

"Tough shit. There's no way in hell I'm ever allowing you within fifty yards of Red Bull again after...May." There's the echo of horror in his pale eyes and a gruff quality to his voice when he says May.

The whole pack says it like that, really, which Stiles finds deeply unnecessary. He wasn't that bad. Besides, he's pretty sure it was the Five Hour Energy shots more than the Red Bull that was to blame for May. But, you know. It was finals. Everyone does crazy shit during finals week.

Derek interrupts his internal pouting by getting to his feet — pushing against Stiles' thigh to help himself up... rude — and is striding toward the planning table to get the laptop when he calls over his shoulder, "You can have unlimited tap water and left over spaghetti instead."

"Ugh." Stiles rolls his eyes, slumping against the back of the couch. "How am I supposed to get anything accomplished working in these sorts of primitive conditions?" He gestures pointedly around the barely furnished loft to emphasize his point.

Derek looks like he wants to drop the laptop on Stiles' head but resists, gently setting it on his lap instead. There's a pulse-ratchetting moment where his hand lingers near Stiles' groin before he shakes his head and takes two extra large steps back.

Stiles very manfully does not mention it and instead gets straight to work. For over two hours, he scours the depths of the internet in search of information. He doesn't stop until he's got fifteen tabs open — and only two of them are explicit PWP fics from Vampire Diaries fandom.

Shoving the computer off his lap, he stands up and twists side to side, trying to work the kinks out of his spine. Derek's head snaps up unnaturally fast, eyes hyper-focused and nostrils flaring. After a beat, he straightens, the predatory gaze dropping off his face before he asks, "Did you find something?"

"Well, it's slightly less informative than when we were trying to research True Alphas." And hadn't that been a shit fest? Stiles watches Derek's face fall before he offers a lifeline. "But there might be a connection to something else."

And then, because he's been thinking about it, Stiles says, "Hey, apropos of nothing I just researched, but that whole...chatting with your mom from the great beyond thing. Any chance you could call her up and maybe ask her what to do?"

Derek's expression morphs wildly from elation at the memory of seeing his mom straight into despair before he shakes his head. "No. Peter took her claws and..."

Stiles places a gentle hand on Derek's arm because he knows. He knows. He'd give his left nut for a chance to see his mom again. Hell, he'd go fully fem!Stiles for that opportunity. He tries not to think about the pure jealousy that had burned in him upon hearing about Derek seeing his mom again. It had not been one of his finer moments.

Clearing his throat, he shrugs and nods. "Okay, while that would have been easier, I think probably what we need to do is treat your full shift self like a ... well, like a wolf."

"But," Derek says, holding up a finger, his voice all smarmy, "it's not just happening when I shift. It's my unshifted form that's having issues. My human form."

If Stiles had a pencil, he'd be snapping it in half right now. Slowly and clearly, he enunciates, "Right, but the catalyst is the wolf. Not the human. And it's the wolf we need to bring in alignment with your human instincts."

Derek's still looking skeptical, but Stiles is having none of his shit. Not while he's still having tingly flashbacks to what happened in the kitchen.

"Look," Stiles says, voice as even as possible, "when natural wolves go through this, they get rid of that pubescent energy by wrestling, play-fighting, and rutting against pack members."

Derek scrubs a hand down his face. "But the point is, I want to learn how not to sexually molest the pack." He drops his eyes, cheeks and ears going ruddy again. "I was actually hoping that they wouldn't have to… know. About this."

Stiles shrugs, trying for nonchalance when he says, "Yeah, I mean. I know. I get it, dude, really. But think about it. I'm pack and it's not like I don't already know. Use me."

Derek slowly looks up, his expression perfectly blank.

Spreading his hands in a dramatic 'ta-da' motion, Stiles offers, "I don't mind being your rutting buddy. The butt you rut."

The silence that falls feels oppressive, heavy with the weight of a thousand regrets. The butt you rut echoes in Stiles' head over and over until he has to put his hands over his ears and squeeze.

"So I'll leave then. Now," he finally blurts, leaping from the couch, his feet itching to carry his mortified body out the door. "I'm just gonna—"

"Yes." Derek's soft, disbelieving-sounding voice barely cuts through Stiles' panic, but when it does, Stiles is still backing away. Derek clears his throat and nods, a little staccato dip dip dip of his chin. "I mean. Okay."

"Okay?" Stiles looks behind himself at the door, then back to Derek, eyes zeroing in on his crotch before he yanks his gaze up, feeling the strain in his eye muscles. "Okay you want me to leave or okay..."

"Okay to the uh... to the butt thing."

And then they're both cringing and oh god, the awkward is overwhelming. But this was Stiles' idea, so he knows he has to man up. Lead them forward. Advance the guard or whatever. Possibly gird his loins. He wishes in a very abstract way that he knew what the fuck 'to gird' meant.

Oh well, nothing for it now but to push forward. The only problem is that Stiles isn't exactly feeling the sexy times now, and from the look on Derek's face, it's obviously the furthest thing from his mind too, so Stiles lets out a loud war whoop and jumps at Derek, arms extended.

Only Derek doesn't really move, so Stiles just kinda hyperextends his left elbow and ends up flipping over the back of the couch and onto the floor where he lays, blinking at the ceiling. Derek's face appears in his field of view, looking two parts disgruntled, one and a half parts perturbed and maybe one-eighth of a part concerned, with all the rest dedicated to constipated confusion.

"I know you're not experienced at this, Stiles, but what the hell was that?"

Scowling, Stiles slaps away the hand Derek holds down for him and scrambles to his feet, opening and closing his elbow to work out the kink. "I figured we'd start with wrestling and work around to the other."

"Maybe you could clue me in on your plans next time so you don't hurt yourself?"

"Yeah, you know what? Fuck you," Stiles grumbles, stomping towards the kitchen. Yanking open the refrigerator, he leans in to grab a can of coke only to let out a yelp when Derek starts rubbing up on him again.

"New plan," Derek gasps, yanking Stiles back and slamming the door shut.

"Yeah." Stiles' head drops back, landing on Derek's shoulder. "I noticed. What the fuck, man? Is it something about me being in the kitchen? Does that do it for you? The domestic thing?"

"God, shut up! You're so fucking annoying. Just be a quiet butt for me to rut, okay?"

"What, unnhh." Stiles goes quiet, licking his lips as arousal explodes to life inside him, blending with the anger he'd been feeling and mixing it all up into some kind of animalistic need. He reaches back, gets a handful of Derek's hair and pulls, not bothering to be careful. "What makes you think I'm in the mood for rutting?" he snarls, shoving his hips back as Derek grinds forward. "Maybe I want to fight instead."

But apparently the challenge appeals to Derek because he sinks teeth into the back of Stiles' neck and manhandles him straight to the floor, unclenching his jaw only when Stiles' cheekbone smacks the cold tile. Derek grunts then, one hand splayed out on Stiles' upper back to pin him in place while the other grabs his hip, yanking upward until he's folded up into some kind of fucked up downward dog yoga pose.

A low rumbling sound fills the air, raising the hair on the back of Stiles' neck, and Derek's hand slides slowly along his back until it hits the waistband of the old sweatpants he's wearing. They start to slide down over the curve of his ass and Stiles can't stop himself from lifting his ass just that little bit higher. He's gleaned enough about natural wolves to know exactly what he's doing. Maybe later, he'll be mortified at the thought of just presenting like a bitch in heat, but for now, he's a little wrapped up in what is without a doubt the hottest fucking thing that has ever happened to him.

Derek drags the waistband of his sweats lower until it hits the top of his thighs, baring his boxer brief-covered ass to Derek's gaze. He smooths both of his hands over the globes of Stiles' ass cheeks the grabs handfuls of flesh, squeezing and kneading until Stiles is nearly folded in half in his need to push his ass higher.

Derek's teeth are there, nipping the inside of one cheek through the thin cotton, then the other side before he digs his chin into Stiles' crack. Dragging it low, he opens his mouth right over Stiles' hole, the moisture from his ragged breaths dampening the material before he starts mouthing at the material, driving Stiles right out of his mind.

It's hot and rough and wet, and Stiles may as well be naked for all the good his underwear are doing. Stiles' eyes roll open, his up close view of the bottom of Derek's refrigerator gone fuzzy as his gaze focuses on the condensation his punched-out breaths are leaving on the tiles. And then he can't breathe anymore because Derek's tongue is licking at his hole, stabbing and furling and flattening out to lap at him before going through it all over again.

"So wet," Derek moans into his ass, and Stiles would laugh and say something about whose fault that is but the way Derek says that, so lost and enthralled, goes right to his dick.

His dick that's been hard as nails since the refrigerator door slammed closed. He can feel how wet and sticky his underwear are from the precome that's been steadily bubbling up, and he doesn't even think before he gasps, "So wet for you."

Derek goes still, and the rumbling gets louder, resonates in Stiles bones now. In a hot second, Derek's grip on his hips gets tight enough to bruise and his face disappears before he's yanking Stiles backward, pulling him in tight. Derek's upper body folds over Stiles' and his dick is there again, grinding against Stiles' wet ass, making a place for itself.

Over and over, his body rocks hard against Stiles, and there are going to be bruises on his knees and his cheek, but he doesn't fucking care. He just gets his hands up under his shoulders, sweaty palms slipping against the tile as he pushes back into each thrust, growling and snapping himself in frustration.

Their clothes are a barrier that Stiles wants gone, disappeared. He reaches back, wedges his hand between their bodies to get at Derek's button and zip, but Derek snarls, biting his shoulder in warning.

"I want your dick," Stiles grits out through his teeth, pushing back even harder in retaliation. "Give me your fucking dick."

Derek chuffs right behind his ear, the breath hitting the sensitive skin and sending lightning bolts of sensation zinging along his nerve endings. Then his teeth are fitting over the back of his neck again, and Stiles can't stop his body from going lax, pliant.

"Good bitch," Derek mumbles, fitting his calves on the outside of Stiles', arms wrapping up under Stiles' chest to grip his shoulders, locking them together and using that hold to slam Stiles' body back into his brutal, bone-rattling thrusts.

"Good," he mutters, slamming his hips forward, "bitch." And then, even through the restriction of Derek's jeans, Stiles can feel his hard dick swelling, and swelling some more, until it feels enormous, pushing Stiles' ass cheeks wide on just the girth alone.

"Holy shit, holy shit," Stiles chants, all the energy that had gone quiet and complacent roaring back through him. "What is going on with your dick?" And then his brain comes back online just long enough for him to squeak, "Oh Jesus, you have a knot!" And that's it, he's gone. The combination of his prolonged arousal, their frantic grinding, and this new, overwhelming knowledge combine to send him flailing over the edge of sanity straight into a black-out orgasm.

When he comes back to himself, they're on their sides, Derek still a hot length all against his back. He's mouthing at Stiles' neck, one hand cupping Stiles' softened dick through his come-soaked underwear while the other smooths gently back and forth over Stiles' chest, occasionally glancing over one of his nipples.

Derek must realize that Stiles is back with him because he sighs heavily, the hot, humid air blasting the back of Stiles' neck, and says, "Really?"

"Hmm?" Stiles would speak, but he just kind of...can't. It's like his tongue is glued to the roof of his mouth. Instead, he shimmies back against Derek, a hazy part of him luxuriating in the fact that Derek's still all hard and knotted up against him.

"My knot is what does it for you?" The tone of judgment in his voice is uncalled for enough that Stiles' tongue rejoins the party.

"Fuck you, dude. The guy with the knot doesn't get to judge the guy helping a bro out. Besides. Scott said he didn't have one, that lying liar."

At the mention of Scott's name, Derek growls and tightens his arm around Stiles. Then Derek lightly licks over the raw place on the back of Stiles' neck and says, sounding way too smug, "He doesn't."

"Ah. Is it a born wolf thing?" Then, because he's an asshole to likes to poke bears — or, you know, werewolves — Stiles says, "Yeah, Peter seemed like he had a great big knot." Of course, Stiles immediately regrets that because no sooner have the words left his mouth than Derek is practically chewing on his neck, little growls bursting from him randomly.

"Ow, hey, stop that. My young, tender flesh is very human. I don't heal like you do, asshole."

And then Derek goes stiff and perfectly still. Stiles has a moment to regret saying that, assuming Derek's worried about the fragile human, before Derek pulls him closer and groans like a man facing death.

"Jesus Christ," he mutters. "Why is it always you?"


"Why are you always the reason I go to jail?" Derek knocks his forehead against Stiles' shoulder and Stiles has a moment to feel a slight twinge of guilt.

"What the hell are you talking about, dude? I'm over eighteen! This is no longer a felony. Wooo."

Derek just pulls him closer and grumbles for a bit about his wolf's bad taste.

"So," Stiles says when it feels like Derek's dick is back to normal sized. "When, uh," he waves a hand to indicate their relative positions, "when should my butt be available for you to rut again?"

"Is never a good time?" Derek growls, though Stiles can't help but note that he's already chubbing up again.

"Yeah, somehow I don't think Junior's on board with that plan. Or maybe he just doesn't mind my particular brand of charm." Stiles wriggles against Derek, grinning to himself.

"You are the exact opposite of charming," Derek groans, buts rolls them back over so he can mount Stiles again.

Stiles makes a mental note to carry knee pads and a pillow everywhere for a while before the ability to think at all dissolves away completely.