A/N: Written for comment_fic on LiveJournal from a prompt by mangacrack.
The first time they kiss, it's a frantic press of lips in the basement of a dilapidated Colonial where Sam had been trapped by the house's resident angry spirit. Sam's not sure which of them moves first; after a second he realizes that it doesn't matter. Nothing matters but Gabriel's too-hot mouth against his own, Gabriel's hands running up his back to clench tightly in the fabric of his jacket, the feel of Gabriel pressed close against his body.
Then Dean's boots are banging against the steps, and they break apart. By the time he's down the stairs, Gabriel's checking the gash on the back of Sam's head and making worried, totally platonic noises. Neither of them says anything.
It's a week before they kiss again. This time, Sam doesn't have the excuse of being concussed and in mortal danger. The only danger is that Dean could come out of the bathroom at any minute. Sam thinks Gabriel likes the risk, likes the fact that they're standing in the middle of their motel room with the curtains open and his brother one thin wall away. It doesn't take much for Sam to decide he likes it too.
They don't talk about it, don't try and put anything into words, and Sam's okay with that. There's a nagging worry in the back of his mind that if they try and look too hard at whatever it is that they have, it'll pop like a soap bubble in the sun, because Sam's no good at relationships, not anymore.
He needs this, no apocalypse, no demons, just him and Gabriel and a tiny stretch of time where he can forget about everything else.
He'll worry about the rest later.