The word was loud, even pressed into Derek's palm. There was no one around to hear them, though. Stiles would argue that the Holy God himself was, just to get the umph back in Derek's thrusts (he'd slowed down, so they didn't smack when their skin met).
What they did was a Sunday thing. They saw not hide nor hair of each other Monday through Saturday, but come Sunday - they were folding themselves into Father Argent's confessional booth. Stiles didn't like him - made a point of spilling over where he would sit, with a toothy grin that bit into his lower lip. Derek didn't help the matter - and from time to time, spurred him, whispering encouragement into the slick skin of his back (the booth got hot - and even though they didn't have the time for a strip fuck, they did it anyway).
"Quiet." Derek's voice was rough, from the heat in his throat that tasted like the heady quirk of Stiles. He stopped moving entirely, and Stiles keened, exhaling heavily and inhaling a gasp thereafter - sharp and crisp; no where near the fresh, cool air he wanted. But he took it, anyway.
It was hard to concentrate on being quiet when Derek's hand was resting hot and damp on the low of his stomach, where his breathing was heaving most.
"Unless..." Everything sounded like an announcement, there. Stiles knew on good will that they were alone - the church, empty. Boyd was a good sport, and always knew how to clear a room for them. It was a pain in the ass for his wallet, but worth it. Stiles gave a minuscule roll of his bones, back against Derek, just enough to remind Derek that - hello. Dick. In his ass. All up in there. Yeah. Hi.
Derek growled, and twitched up. It wasn’t enough to give Stiles the exact grate he had wanted, but beggars couldn’t be choosers. Or something.
"Unless you like taking the Lord's name in vain."
Stiles groaned, the sound stressed. It was too hot, his skin flushed to reflect the atmosphere. Derek's fingers crooked to graze his nails over the hole his belly button made, before flattening them again. His palm stroked up his chest, and Stiles nearly choked on freaking air when the sweaty-slide of his thumb nudged his nipple.
"Is that what you like?" Derek asked, low and ruined and Stiles remembered every occasion his father would comment in regard to Derek being a saint and thought - fuck that noise.
Which - he supposed, would make his ass the noise. Damnit.
"I am thinking way too much," He breathed, tongue feeling too big for his cheeks and teeth. "Which means - you're not doing something ri-hiiite." His voice went up towards the end, because something different in temperature was against his dick, coiling up - and half of him was composed of horror and the other half with the temptation to laugh because shit. That was Derek's fucking rosary.
He wore that around his neck, oh, God.
"Do you?" Derek prompted again, and his tone was so don't make me ask again that the head of Stiles' dick gave a happy little twitch. Traitor. His answer didn't come fast enough - and Derek's hand was moving, and the sensation of the rosary rolling along his dick made him make some strange yip in the back of his throat, that he was sure was meant to be a keen or something - but just lost its way.
"Yes!" He didn't like talking during sex. He loved talking, he really did - but he liked noise more - liked the grunt of Derek's effort in his ear and the heavy fall of their breath in the enclosed space around them. “Oh, fuck, yeah,” Derek was moving again - Hallelujah! - and Stiles eagerly moved with him, tilting his head back. His arms were shaking, hands shoved up against the walls for balance. They always did it that way - Stiles, with his hands out, braced, legs spread to accommodate the space of Derek’s seated hips, one leg up for angling purposes, and Derek - sitting, getting the easy fucking ride of his life.
For that, Stiles usually made him wear a condom (to miss out on filling up his ass, and then getting the agony of disposing of it in a church). Safe sex was the best sex, but they were both clean - he knew it, because as scarce as their encounters were, they were mutual and exclusive.
Derek smacked the thigh of his raised leg, the sound sharp. It startled Stiles into another pitch of a noise, ass clenching and hips jerking around Derek.
“I said - you’re such a sinner. Aren’t you? You drank the Devil’s water,” Oh, Jesus Christ, that shouldn’t be as hot as it was - “And it poisoned you. You took the Lord’s name in vain, swore under his house.” Derek moved his hand back to Stiles’ dick, and pulled the rosary in a way that it tightened around the base of his dick. Like some way-too-kinky cock-ring. Stiles moaned. “You used that pretty pink mouth and sucked my dick, too.”
“You like doing that? You like to sin, boy?”
Doomed. That’s what he was. Utterly and so pleasantly.
Stiles nodded, not too sure when his breathing had turned into bitch-like panting, “Yes.”
“Tell me,” Derek goaded, something along the lines of gentle, and his rocking was slow but delicious. It was grazing spots inside Stiles that pulled his muscles and made him want to switch a flip into “wild abandon” mode - fuck until he hurt. “Tell me what you like doing.”
“I like sinning.” The admittance was a whimper - mostly for effect, half because the sound was a truth.
Derek’s form of a reward was cinching the circle of his hand around his cock.
“Good boy,” he murmured, and it was rough. Like he needed water, but would much rather bite into Stiles’ skin. He did, he realized belatedly, because a spot near the center of his back felt prickled like it’d been pinched by teeth. “Are you going to ask?” His thumb rose up, and nuzzled the tip of his dick. Pre-cum ducked away from the pressure-fall, and Stiles chanced a glance down. Derek smeared it over one of the rosary balls and Stiles made a noise of interest. “Ask, for your forgiveness? And then maybe the Lord will see it in himself to let me make you come.”
“Deus - me! - i-gnoscat,” Stiles said, mostly to be a smart-ass, but he wasn’t sure if that meant it backfired when Derek pistoned up into him. It milked a keen from him. Derek mellowed out again when he was through, and Stiles could feel his own frantic pace of breath on his collarbone.
“Not that one.” Derek delivered a soothing pump to his length. “Decade.” Stiles turned his head, just enough to glower over his shoulder.
Derek’s shoulders were set back, looking for all the world as if he were relaxed, but he could read the glint in his eye. His hair, always unmarred by product for church, was curling against his forehead, wet with sweat. He looked more like a mess than a good boy, and Stiles felt a thrill that he’d done that. Well, mostly, his ass, but still. Him. Part of him.
So Stiles began with, “O my Jesus,” and Derek tensed, rocked up into him, timed it to the lazy lift-and-fall of his hand.
“In Latin,” he interjected, as Stiles touched into forgive our sins.
“O mi lesu,” he began again, and dimitte nobis debita nostra was cut into a long moan when Derek tugged the rosary. It gave a sharp pinch, and Stiles bucked into it.
“L-libera no-” He drew out the O when the head of Derek’s cock nudged into his prostate, “-s abe i-gne - ahhh,” He bit his tongue, so he didn’t say shit and fuck it up, “inferni,”
“You’re almost there,” Derek mumbled, sounding wrecked. Sick bastard. (But the thought was fond.)
“Conduc in - caelum! - omnes animas, Oh, oh,” Stiles shoved his fist into the wall, and it made a soft clunk. Derek chuckled, behind him, but it was so faint that Stiles wasn’t actually certain the sound had existed. “Pra -- esertim,” He panted, and ducked his head, shoulders shaking. His thighs were quivering, and Derek moved his hand from where it had been braced over Stiles’ heart to his leg, rubbing the muscle where it was clenching into a knot.
“Good boy.” Derek’s praise coiled heat in the pit of his stomach, and his cock was aiding with the sensation, the hot, sharp juts into him. The sound of their skin meeting was a constant now, no longer the ragged tune of their chests working. Stiles’ lungs ached to match the rest of him.
Good, he thought.
“Illa-aaah-s, quae,” He licked his lips, thought of water, then of cum, and keened, shoving himself back to meet Derek’s rough gyrate upward. “Maxime indigent,” Derek made a noise, and Stiles knew it was real, this time, because it was in his ear, and Derek had moved his hand in favor of wrapping his arm around Stiles’ waist. It tossed Stiles’ balance, brought him down in a full seat. His arms fell away, and he pressed a hand up towards the right wall of the back of the booth.
“Misssssericodi-aaah,” Oil and fire were introduced in the pool of his groin, catching into impossible fire that sprawled out into his thighs, delved down towards his balls. Derek was frantic in pace, up and up and always up, his fingers fumbling for the rosary and unwinding them - “Tua. A-amen!”
And he was free, but he still needed - and Derek was graced with the knowledge of it. He was thrumming, and the sweat made them stick and snap, sharp, skin and skin. Derek’s hand was slickened by the prior leak of him, fast and messy and everything slippery coaxing him into a blissful, wild arch and spasm.
He came with a loud sound, that reverberated not just through the space of their booth. Most of it fell to curl through Derek’s fingers as he stroked him, the rest of the ropey gouts leaping for the wall. Even as the white-flare-bliss clenched in his head, in his entire being - he still fucked back onto Derek, until Derek let out his own cry and he felt heat, hotter than the air that sat on their skin, slick his insides into more noise. A wet glide that Derek didn’t stop the force of until a good minute after.
By then, Stiles was stroking his legs, trying to calm the spasms there. He always got the charlie-horse effect, when he came back from a good visit on cloud-nine, which sucked for the awkward return home. His dad always had a quirked brow for the mannerism, and Stiles was never keen to answer.
The booth was still too hot for their proximity when Derek began kissing a jagged line up his back, like that would sooth the drag in-out of Stiles’ breathing. He pressed an Amen into a knot of Stiles’ spine, and Stiles snorted.
“You wanna talk about Sin?” Stiles fumbled his words, tongue heavy and sluggish; revolting its use. His bones were exhausted. The marrow, even. “Because - seriously. You’re the one who walks into Church with a fucking tube of lube in his pocket.”
Derek laughed, and it rang out loud through the Church.