Written for the following prompt on the kinkmeme:

I desperately need some good old John/Sherlock car lovings. One of the two of them (your choice!) really loves cars and when a case takes them to a garage filled with gorgeous cars it's a bit overwhelming. Extra points for rutting on the hood of anything particularly sexy.

"There he is, Lestrade. Wallace Banks - mechanic, fraudster, and two-time murderer. Right where I said he'd be." Sherlock points imperiously towards the corner, where a man in greasy coveralls is wiping a spanner with a filthy rag. He stammers once or twice before attempting to make a run for it, but the team from NSY are quicker than he is, and they knock him to the ground and cuff him before he has the opportunity to get away.

"You can take him away, John and I are just going to look around for a moment, make sure there's nothing we've missed." Sherlock gestures and John goes trotting off behind him to the other side of the garage, towards a second area with a few classic cars in various states of restoration. There's a gorgeous selection of British and American vehicles. John's eyes drag along the low, prominent haunches and distinctive t-scoop bonnet of a 1972 Dodge Challenger, threatening in flat black. His gaze strokes over the subtle elegance of a deep rich cobalt-blue and silver two-tone 1963 Bentley S3, the elaborate front grill smiling invitingly at him.

Suddenly, his attention is diverted when they turn a corner. In one of the bays is a mint-condition 1967 convertible E-Type Jaguar roadster. The British Racing Green paint is immaculate, the whitewall tyres must be new because they are pristine. The interior is a lush beige leather, perfectly setting off the rich emerald paint and gleaming chrome accents. John's not sure he's ever seen anything so gorgeous in his life, with the possible exception of his flatmate and lover. He may not have a driver's permit, but he's always been able to appreciate the aesthetics and the mechanics of a particularly excellent automobile, and here in front of him is the pinnacle of British design and engineering.

John leans forward, resting his hands on the bonnet of the gorgeous machine. His mind has been wandering while Sherlock finished up with Lestrade, fantasizing about the Jaguar and all the things he wants to do on it. By the time Sherlock slinks up behind him, he's awkwardly half-hard, and trying to surreptitiously adjust himself in his jeans. Feeling Sherlock's warm breath at his ear isn't helping matters, either.

"John Hamish Watson, are you aroused by these cars?" Sherlock sounds amused, but his voice has taken on the slightly ragged edge that makes it obvious he finds the idea somewhat exciting.

John flushes, and looks away, absently stroking the chrome above the car's headlamp in an impossibly erotic manner. It's obvious he's not doing it on purpose, but the gesture goes straight to Sherlock's groin.

"Yes..." John mumbles. "Well.. not exactly. It's a gorgeous car, I've always loved the lines on it. It's been compared to male genitalia, and not without merit. Long, proud, slightly menacing - " His voice hitches. "But mostly, I've just fantasized about being taken over the bonnet." John bites his lip, embarrassed, and it's all Sherlock can do not to grab him and pull that lip into his own mouth. Something about seeing John so vulnerable like this - and his word choice, being taken, does not escape Sherlock's sharp ear - is driving Sherlock absolutely wild. More often than not John is the one in control of the more physical aspects of their relationship, and Sherlock is fine with that, but something about this sudden role reversal goes straight to his reptile brain. He pulls his coat open, leaning forward and pressing his swelling cock against the gentle curve of John's arse.

"You know..." he whispers, trailing a line of kisses along the side of John's throat. "The garage was empty when we came in, save for Mr. Banks, the mechanic, who is now in police custody. They've cleared the crime scene, and headed out. Lestrade showed me how to enable the alarm whenever we head out."

"Mm.. and?" John's mind is clouded, distracted, as his fingers slide across the highly waxed bonnet of the car. He's trying to think of why this might all be relevant, but it's hard to focus while he's trapped between the Jag and the slow, gentle grinding of Sherlock's cock.

"And, John, that means we are entirely alone in here." Sherlock's murmur has - impossibly - dropped an octave from its usual pitch, and he's rumbling against John's throat. He reaches around and very lightly traces John's prick through the fabric of his jeans, causing him to whimper and rock back against Sherlock.

Tongue darting out over his lower lip, John pauses. "Sherlock, I'm not so sure that's a good idea..." He's trying to behave, but he can feel his resolve wavering as Sherlock's skilled fingers stroke and trace the prominence of his erection. Before John has time to talk himself out of this, he mumbles his assent and presses back against Sherlock again. That's all the incentive the taller man needs, and within seconds he's undone John's flies and is pulling his jeans down around his muscular thighs, lightly dusted with gold hair.

Deftly, Sherlock works one hand into the front of John's pants, stroking his cock with light teasing strokes. With his other hand, he undoes his own trousers and slides his pants down, freeing his own erection. Bobbing forward, it brushes against the thin cotton of John's undergarments, rubbing against his arse, and both men moan softly.

"Ugnh... Sherlock..." John grunts softly as Sherlock's fingers encircle the head of his cock, stroking just lightly enough to keep him distracted. "Lube?" Smirking into the soft flesh of John's neck, Sherlock reaches into the pocket of his coat and pulls out a small tube, before letting the coat fall to the floor.

"Prepared for anything, aren't you?" John chuckles.

The two men fumble for a moment, working together to free John from his pants. Once they're down around his thighs, along with his jeans, Sherlock just presses up against him, the both of them relishing the skin-to-skin contact for a moment. At the familiar sound of Sherlock slicking up his fingers, John drops his head and braces himself against the front end of the car. Too eager now for drawn-out foreplay, Sherlock slides two moist fingers down the cleft of John's arse, tracing the puckered ring of muscle while his other hand reaches over John's hip and strokes him tightly. Gently, Sherlock slides one finger into John. Encountering little in the way of resistance, he thrusts the finger in and out several times, rocking his wrist and loosening him further.

As the circle of Sherlock's fingers slides along the length of John's cock, John finds himself rocking his hip back and forth. Each forward thrust drives him back through the snug grip of Sherlock's hand, each backward thrust drives the finger deeper into him, until he's whimpering. Encouraged, Sherlock slides a second finger into John, followed almost immediately by a third. He sets a firm pace, fucking John open and gently curling and uncurling his fingers until he feels the muscle slacken.

"Sh- nngh- Sh'lock.. hurry, please." John's voice, thick with want, hitches as he pleads with Sherlock. The desperation goes straight to Sherlock's groin, his cock twitching in anticipation. He relinquishes his grip on John's erection and slowly slides his other hand away from John's arsehole, earning a muffled, anguished groan. Both hands free, Sherlock coats his prick liberally with lubricant, smearing a bit more around John's entrance before lining himself up.

One hand guiding him, the other tightly gripping John's hip, Sherlock slides in as slowly as he can. John's whine, needy and eager, makes it clear that's he's comfortable and ready for more, and Sherlock pulls out until just the flushed head of his cock is inside John, and then slams back in roughly. John throws his head back, keening softly as he revels in the stretch of Sherlock thrusting into him. His hands, sweating now, slide against the car and John leans further forward, pulling Sherlock with him as they're locked together.

Despite their height differences, Sherlock has managed to slide even deeper into John and push him down onto the bonnet, pinning him against the car with each thrust. The motion's causing John's hot, hard cock to rut against the Jag, smearing traces of pre-come over the gleaming paint.

Sherlock's pace is steady and deep, and it's not long before John is moaning and murmuring incoherently. There's a thin trickle of sweat soaking the small of Sherlock's back, and John's hair is damp. Sherlock pulls out entirely before slamming himself back in, burying himself again and again, spurring the both of them closer and closer to orgasm. Desperate now, Sherlock's fucking faster and deeper, the bulbous head of his cock stroking against John's prostate with each thrust. He leans further forward, hands entwining with John's on the bonnet. Arching his back so his lips are level with John's ear, he murmurs.

"John, I want to see you climax all over this car. I want to see your come splattered across her." He slides one hand between John and the Jag, gripping the base of John's throbbing cock and stroking quickly and roughly.

John's never been able to refuse a request from Sherlock, and within seconds he's clenching his muscles around Sherlock's cock, head thrown back as he lets out one sharp, carnal cry. John shudders as his prick twitches, as his seed spills across the deep green paint. Sherlock groans as he feels John tighten around him, thrusting once, twice, and he's there, violent orgasm rippling through him as he comes buried deep inside of John.

They lay limp across the bonnet of the car for a moment, catching their breath, when John starts giggling.

"Sherlock, get off, we've got to get out of here."

With a forlorn little sigh, he pulls out and straightens up, tossing a handkerchief at John, who makes quick work of wiping up the bonnet of the Jaguar as best he can. They're just tucking themselves away and neatening up when they hear Lestrade's familiar footfalls coming towards the back of the garage.

"Oi, you two. Still here?"

"I could say the same for you." Sherlock grumbles, still not entirely composed.

"I just left some papers here." As he passes the Jaguar to go pick up the forgotten documents, Lestrade notices the handprints and smudges all over the bonnet.

"Sherlock, did you notice those earlier? Do we know if they're relevant to the investigation?"

John coughs, a hot red flush creeping up his neck and ears. Sherlock just shakes his head and does his best to steer Lestrade away from the car.

"No, not relevant, not at all. Carry on, just ignore this. We were just leaving, have a good evening, Inspector. Come on, John." He grabs John by the arm and drags him towards the door, leaving a confused DI in their wake.