He doesn't know what he's doing when he pins Desmond against the walls of the dilapidated estate. Hell, he doesn't even know why he followed him outside in the first place. All he knows is that he needs this, needs to be this damn close to the irritating prat, needs to be breathing in the same damn air as him and ohgodwhydidhesmellsogood?
He darts out his tongue to nervously wet his lips as Desmond tries to shove him away, watching from behind his glasses as the annoying(mostlikelyprobably) words form on that tantilizing, scarred mouth and he can't fucking help himself from leaning in and kissing away every syllable, because right now they don't need to talk, they just need this.
And Desmond /does/ need it, he reminds himself. He needs an outlet just as bad as Shaun does, because Rebecca and Lucy aren't the only ones that hear his screaming at night. The thought is all the convincing he needs as he dips in further, lips, teeth, and tongue trying to draw out the poison that was the bleeding effect, hands working to undo the other's pants. There wasn't enough time to spare to be a gentleman and it's not like Shaun would /anyway/- not with him.
He finds it arousing and just a little bit endearing when Desmond finally relaxes into him, protests lost in the low, moan that he makes when Shaun is pumping his cock into complete hardness. Desmond's head tosses back against the wall when he rubs his thumb over the tip- an act that leaves Shaun breathless and gulping down his anticipation.
He's fumbling as he tries to get out of his slacks, something that causes Desmond to /laugh/ at him and there must be something wrong with him- maybe Desmond had some god awful drug on his lips- because he's laughing too, laughing as he exposes his aching length and captures Desmond in another kiss. He can feel his heart flutter, but whether it was the adrenaline or something else Shaun would never know because he can't question such things in the middle of /this/, whatever the bloody hell this was.
When he finally enters Desmond the feeling is unbelievable and he shudders, hard, and tries to drink up all the delicious sounds Desmond is making because of it- because of him. And when he moves, Christ, the feeling is like nothing he has ever felt before and he's rocking his hips into him as fast as he could, savoring the way Desmond's legs are wrapped around him, savoring the way Desmond writhes against that wall, looking as sexy as anyone possibly could.
Their orgasm comes within a matter of minutes, the two of them crying out into each other's mouths as they tensed and shuddered and released and Shaun swears he's gone blind for the moment because all he can see is stars.
They stand like that for awhile, panting and stuck together from sweat and semen, until Desmond makes a little, awkward sound that Shaun would find cute if it came from anybody else. So Shaun pulls out and lets Desmond down, clearing his throat, glasses askew and foggy from the heat between them, eyes averting and cheeks maybe just a little pink.
They don't look at each other as they dress, and Shaun thinks that it might have something to do with, gee, who knows, the fact that he had fucked him against the wall of his ancestor's estate for apparently no reason.
They leave after that, making sure to enter the estate only when it wouldn't be deemed suspicious, and maybejustmaybe Shaun is a little disappointed at how easily Desmond seemed to brush off the encounter. But then Shaun reminds himself that Desmond is annoying and stupid and certainly nobody he should ever really care about like that, so he assumes his mask of sarcasm and wit once more.
Lucy knows something happened, from the look she gave him when he reentered the chamber, and Shaun simply dips his head and shrugs as if he had no idea what she was talking- er, looking about. So she shakes her head with that funny little smile and Shaun scoffs to himself and goes back to work, as if nothing has changed, as if he didn't just screw Desmond against the wall just outside of their hideout.
When night rolls around, Shaun is only mildly surprised when his door opens and a warm figure crawls into bed with him, mumbling stupid little excuses that Shaun quiets with his mouth, hoping that Desmond will realize that he was actually saying "yeah, hey, I guess I don't hate you after all and I quite fancy you and there's really no way that I can say it other than this."
When Shaun feels Desmond smile against him, he reads it as "I know."