Okay, so there’s a tiny possibility that Derek’s broken his dick. Not, like, literally broken, just figuratively. See, after that whole thing with Derek wrapping up his hands with his own belt — why hello there, bondage kink, so very nice to meet you — Stiles has kind of been a little obsessed. He’s jerked off while wearing it, jerked off while he’s got his hands wrapped up in it, jerked off to the smell of the leather, and jerked off to the mental image of Derek coming all over it while Stiles has his hands wrapped up in it.
Like the ocean is a little wet, the sun is a little warm, and space is a little big, he’s a little obsessed.
Which may be why he’s face down on his bed, leather pressed up against his nose and mouth, hand snaked under the band of his boxers, jerking off again. At this rate, he’s going to get friction sores, and it’s all Derek’s fault. He's got his mouth on the belt, tasting the salty-bitter edge, imagining that he's lapping up come. He has his hips up in the air, just enough to give himself access, just enough that he can roll and grind against the mattress.
He feels more than hears the window open, the puff of night air cool on his flushed skin, Derek's sharp inhale making him jump and jerk and shiver.
“What,” he says, and Stiles can tell from Derek’s voice alone when his eyes start to blaze alpha-red, “are you doing?”
Stiles wonders how he looks to Derek, sucking on the edge of that leather belt, rutting into the bed, stripped out of his layers down to just his boxers. His dick is a little dry, but the dark rumble of Derek growling — sexy growling, not scary growling, though to be honest both get Stiles hot and bothered — has him leaking a bead of precome. Stiles angles his wrist, reaches up to catch the bead before it soaks into his boxers, rubs it into the head of his dick with his thumb.
“What does it look like?” Stiles groans from around the belt.
He swears that Derek uses some of that werewolf speed to pounce on him, because in between one stroke and the next, Derek is straddling the back of his thighs. Stiles can feel the hard heat of him digging into his ass, tries to rock up against it, but Derek has him pinned tight to the bed.
“Hold still,” Derek tells him.
And Stiles reaches back to hand him the belt. “Make me.”
Derek hesitates just long enough that Stiles wonders if he's gone too far — though Derek's dick is still very much interested, hello — but then the belt is pulled from his hand. This time, Derek binds his wrists behind his back, not tight, not digging into his skin and leaving marks, like Stiles wants, but tight enough. He pushes Stiles face down into his pillow, pulls him up to his knees so his ass is up in the air, yanks his boxers down and spreads his cheeks with both hands.
Stiles shivers as hot breath puffs against him. He imagines Derek, halfway to wolfed-out, teeth long and sharp and dangerous, caught between the desire to take and claim and have and the need to be careful because breakable human.
Derek presses his face into the crease of Stiles’s ass, licks a long stripe from his balls to his tailbone, blows out a hot breath, and then zeroes in on his target. His tongue dips across the rim, lapping wetly until Stiles is loose and open, and then drilling harder against him. Stiles pants into his pillow, gasping as Derek works his tongue deeper and deeper, bucking at the urge to get something, anything, in his ass right now.
Derek pulls back suddenly, and Stiles’s ass is freezing cold and he whines, “Jesus, Derek, you’re fucking killing me here—”
And just like that, Derek’s on him again, but this time it’s all naked skin on naked skin, and Stiles groans something about stupid unfair werewolves and magical stripping powers that not even he understands, and Derek just holds him in place.
“I said,” he grunts, and Stiles can feel the blunt tip of his dick, hot and ready and all lined up for him, “hold still.”
“And I said make me.”
Derek rocks his hips forward, digs his fingers into Stiles’s hipbones and pulls him back. It’s rough, and there’s just barely enough saliva to make it work, but Stiles is so turned on it almost doesn’t matter. Derek’s dick is a work of goddamn art, he swears — maybe out loud, maybe all in his head — and he gulps as Derek slides in, slow and sure. It takes a dozen or so breaths to take him in, and another until Derek seems satisfied with the angle, and then his hands are off of Stiles’s hipbones and on the motherfucking belt.
“Shit,” Stiles gasps, chest heaving, face nearly buried in his pillow. He’s up on his knees, dick dripping, leather biting into his wrists. He’s not going to last, he thinks wildly, and then Jesusfuckyes Derek’s moving. He starts slowly, like he’s revving an engine or something, delicious heat and friction just edging over into burning and overstimulation territory.
Stiles feels fractured, like he always does, like he can’t quite keep his focus on the awesome things Derek’s body is capable of, and everything starts to break apart into the things his brain can handle at one time. Things like the creak of the bed under them, the bite of the leather into his wrists, the hot jab of Derek fucking him raw, the smell of sweat, the wet sound of Derek spitting and slicking them again and again, his dick leaking everywhere, the white-hot heat coiling up behind his spine—
He rasps out a ragged, animal sound as he comes — untouched, his favorite — and bonelessly slumps forward, spent. Derek lets him go, pulls out with a satisfied grunt, and for a moment Stiles thinks that’s it. It’s so hot, so fucking hot, and this memory is going to stay in Stiles’s personal fantasy folder to jerk off to for-fucking-ever, and—
Derek isn’t done yet. He’s still perched on the bed, hovering behind Stiles, breathing hard and rough. Stiles can just hear the soft slick-slick, feel the rhythmic jerking of Derek bringing himself to the edge and over, and then there’s a hot spurt of come on his back and shoulders and neck. Derek bows his body over Stiles, nips at the base of his neck with too-sharp teeth, and then goes slack on top of him.
Yeah, etching this memory in stone, a monument to the single hottest thing Stiles has ever experienced. He’ll try to remember to get Derek a trophy or something.
Derek eases off of him, slow and heavy, unwinds the belt and lays it next to them on the bed. The belt is spattered in come, too, Stiles notes in satisfaction. When he tastes it next, he won’t have to imagine the salty-bitter taste of Derek on his tongue.
“So,” Derek says, his cheeks flushed, “is this going to be a thing now?”
Stiles rolls over onto his back, pulls Derek down on top of him. “Shut up,” he sighs happily. “It’s your fault.”