Dean isn’t being subtle.
He’s been beating the back of his palm against the underside of his comforter for about five minutes, by Sam’s count, and he hasn’t stopped yet. His self-fingering isn’t blatant, not as bad as he’s seen Dean do it before, but it’s still enough to feel intentional; like he’s daring Sam to inquire within. Sam’s not going to let him win so easily.
He tucks his nose back into the file he printed out at the library on the other side of town, struggling to retain the details of the impossible drowning in the middle of a living room because his mind keeps wandering to what’s going on just three feet away from him. Sam scribbles a sloppy Voodoo? note into the margins, the grip on his pen tightening when he hears Dean to his right, swallowing a moan.
Dean knows he’s awake. Dean can turn his head and see Sam staring at him—maybe glaring would be more accurate—and wordlessly telling him to stop it, but he just hasn’t yet. Instead, he rolls his head back on his pillow, gentle enough for it to look like he’s falling asleep.
Sam wants to pretend that he is actually sleeping, even though he knows better by now. His trick’s working, the way Sam can’t help but imagine how wet Dean must be in his boxers right now and how it’s making him shift uncomfortably in his seat. He glances over at Dean and immediately regrets it when he sees his mouth hanging open. Sam can hear the small breaths coming out of him, quick and soft as he seems to be getting close. His chest rises and falls, heaves like something out of a Victorian novel. Dean screws his eyes shut and clenches his teeth, arching his lower back and letting out a rough, short moan.
It’s an extremely short standoff, all things considered.
Sam discards the file on his bed knowing he can’t make any meaningful progress on the case until he solves his and Dean’s mutual problem. He plops down on top of Dean, surprising him enough that he actually looks nervous for a second as Sam kneels over him.
The shock fades quickly, though, when he drops down to kiss him, hurried and hot, desperate to get off as soon as he possibly can. Then it’s back to work until Dean’s infectious libido catches up to him again.
Sam slips his hand down between them, sliding it underneath Dean’s briefs and wasting no time at all finding his engorged clit. Just a few rough grazes with his fingertips and Dean’s spreading his legs, all but begging for Sam to make him his bitch. Just like always, his plan had worked.
“You’re gross, you know that, right?”
Dean throws him a dewy, lopsided grin.
“You love it.”