Sam Winchester is, if he may say so himself, a pretty good guy. He tries hard to be kind and fair. He wants to see people safe and happy.
And he loves his brother more than just about anything else. He would do anything for him. He takes care of him, worries about him all the time, and he's unbelievably patient with him.
He tolerates Dean's temper. He tolerates his vicious mood swings. His drinking problems, his loud, terrible music, his aggressive driving, his disgusting eating habits, his total lack of motivation to do laundry on a regular basis. He puts up with it all, sometimes with a frown, and often with a fight, but he does put up with it.
Sam Winchester is a very patient man.
But his patience can only go so far. He is now standing outside the motel room door at three AM (cold and wet from rain and having had to walk himself home when Dean took the car from the bar earlier) and looking at a familiar blue necktie dangling from the doorknob.
Now Sam, being the good guy he is, has come to accept the half-romantic, sexual relationship between his older brother and a certain quirky little blue-eyed angel. (In fact, he was the one to get the two of them to cut the crap and "get on with it, already.") He supports them. He's glad that they're happy and all that, he really is.
But right now, he's starting to feel a little less happy and a little less patient, and a little more thangrumpy.
Kicking the door in would be a terrible idea. (He has busted into a motel room once before, under the impression that Castiel was being tortured inside, only to become acquainted with certain parts of his brother's anatomy that he would have happily gone the rest of his life without ever seeing.)
And Dean had convinced him before they went out to leave his wallet in the room with a happy "My treat, Sammy," which left him unable to rent himself another room.
He sighs heavily and glares at the tie. The rain still falls in heavy sheets around him, soaking his clothes further, and doing nothing to quell his frustration. From inside the room, he hears a very satisfied groan, and realizes that no matter what else he's going to do tonight, he has to get away from here.
So with that, Sam Winchester finds himself trudging to the parked Impala, prying the door open, dropping with a wet squishing sound into the passenger's seat, pushing it back to try and fit his long legs under the dash, and muttering a very colorful series of threats against the lovers inside.
He closes his eyes, trying to ignore how sticky his wet clothes feel, and sighs, (even though he knows very well that none of them are going to get any sleep tonight.)
He's a good man, but he's going to kick his brother's ass.