"I don't see why-- ah-- you think you're the one to be on top," the Eleventh Doctor says, clutching at the edge of the console. His shirt hangs open, his bow tie is nowhere to be seen, and his trousers are down around his ankles. "I have much-- nnng-- more experience than you do."
"With things like this?" the Tenth Doctor asks incredulously, licking a long stripe up the side of Eleven's cock. "No you don't."
"You have no way of knowing that," Eleven says. The last word dissolves into a moan as Ten swallows him down, cheeks hollowing and tongue working furiously. His hips snap forward and his fingers tangle in Ten's hair.
Ten removes his mouth with a pop and looks up at his future self, lips red and slick with saliva. "Call it instinct," he says, planting a wet kiss on Eleven's thigh before standing, pressing him against the console with the whole length of his body.
"What d'you mean, instinct?" Eleven is having trouble summoning the right level of incredulity for that question -- understandably, since Ten is biting at his earlobe, practically humming with arousal.
Ten undoes his zip with one hand, the other fumbling at a button in the front of the console. The TARDIS, helpful girl that she is, pops open a little drawer containing exactly the thing he's looking for. "Well, for starters, that outfit's a dead giveaway."
"What's wrong with my outfit?"
"Weeeell, nothing, technically." Ten opens the bottle of lube one-handed, dribbling some over his fingers before nudging Eleven's legs apart with a knee. "Tweed is very fashionable, depending on what century you're in." He slips a finger into his future self, covering Eleven's gasp with a deep kiss.
When they come up for air, two more of Ten's fingers are already working their way into Eleven's arse. "I quite like the way you look, actually, but let's face it, our fashion sense has usually been what you might call eclectic," Ten says, panting a bit. "That isn't the only thing, though. And the other one is really obvious, absolutely staring you in the face."
He pours some lube over his cock, which has been jutting deliciously against Eleven's this whole time, and strokes himself just enough to spread it around. Eleven watches him with wide eyes, and when Ten moves in, lifting Eleven's thigh to get a better angle, Eleven spreads his legs so wide it'd put a professional gymnast to shame.
"Figured it out yet?" he breathes in Eleven's ear, positioning his cock and starting to ease in, just the head at first. Eleven moans and squirms, trying to push himself further onto Ten's cock. When it becomes clear that Ten isn't going to move any further, he shakes his head.
"Well, just look at yourself," Ten says, fucking into Eleven oh-so-slowly. Eleven starts a question that turns into a wordless shout as Ten's cock eases past his prostate. "Panting and writhing like a fifty-first-century porn star." He starts thrusting, picking up the pace and the force until Eleven is clutching at his shoulders, legs wrapped around his waist, head thrown back and pupils blown.
Ten releases his bruising grip on Eleven's thigh to wrap a hand around his cock, stroking roughly in time with his thrusts. Eleven's gasps turn into guttural moans turn into silence -- his throat works, but no sound comes out, as he comes violently over Ten's hand.
Ten moves his hand back to Eleven's hip, leaving a smear of come on the edge of the console, and fucks him hard and fast. Eleven recovers from his orgasm with admirable speed and starts giving as good as he got, planting open-mouthed kisses on the side of Ten's neck. When he bites down just above Ten's collarbone, Ten comes with a shout, collapsing forward and pressing his future self back against the console.
They stay there for a moment, panting in time, the frantic beating of four hearts slowly fading to a more regular rhythm. Eleven drops his head onto Ten's shoulder, and Ten smiles broadly.
"The way I knew you didn't have any more experience than I do," he says, a conspiratorial murmur against Eleven's ear, "That you haven't gotten any since you've been, well, you, is that from the moment you saw me, you were absolutely gagging for it."