The first time he killed a human when no one was possessed, Sam Winchester had convinced himself he had thought the man a demon. It had been dark, he’d been drinking, Ruby’s knife had been in his hand and before he knew differently, the blade had been in the man’s throat. It’d been the fault of the case- getting Dean back- and whiskey. And the man shouldn’t have been walking behind him in an alley.
The second time, he just didn’t stop once the exorcism worked. He told himself it’d been too late, inertia and all. She’d been a pretty girl. Looked like Jess a little if you squinted.
The third, the man had hit on his brother, gotten shot down, and proceeded to slip something in Dean’s drink in response. Sam had half carried Dean to the Impala before he’d lost all control of his motor functions. Dean was safe in the passenger’s seat, slumped against the window. Sam had dragged the scumbag behind the bar and beaten him so bloody even he knew he was pretending when he told himself that maybe the man would survive. If someone had found him and called 911. Within the next two minutes.
It wasn’t until the seventh time that he recognized that he’d targeted women his brother had flirted with in the last four towns (two of which each had one less member when the Winchesters blew out of town). But his brother was back and he wasn’t letting him leave again. It didn’t matter to Sam that Dean seemed to be quicker to reach for a knife than he had been before Hell and that no matter how flat he kept his mouth, his eyes seemed brighter anytime the monster they killed splattered red blood everywhere. Sam loved his brother, maybe now more than ever. He still hid what he was doing. He didn’t stop though.
Five months after Dean had come back, laughter and instincts sharpened, the inevitable happens. Sam has a bowie knife in his hand and a middle aged man tied to a chair, clearly dead not only from the blood loss that must have happened from the wounds on his wrist, but also from the multiple stab wounds to the chest, when Dean walks into the abandoned barn that’s a mere mile away from the cemetery they’d worked in the night before. Sam watches his brother take in the scene while moving towards it - Sam’s literally and liberally red-handed and there isn’t a devil’s trap or binding sigil or anything supernatural in sight. Dean is not five feet from Sam when he puts his gun up. Sam thinks it’s fitting that Dean would shoot him with a gun that had been their father’s.
He doesn’t try to explain, and doesn’t give Dean time to question. Sam closes the space between them quickly, leaning in and kissing his brother’s cheek. “Ave frater moriturus te saluto,” he breathes. After backing away again, he runs the back of his hand over his mouth to get rid of the tickle from Dean’s five o’clock shadow. It was like some sort of torture.
Dean has seen enough gladiator movies to know Sam expects to die by his brother’s hand at that moment; it’s not like he isn’t holding a gun on him and it’s not like this isn’t simply confirming suspicions Dean’s had for the past two months. Before either can react, to the kiss or the decidedly non-church Latin, the door behind Sam opens and the Winchesters hear a terrified “what the f-“ Then two gunshots.
Sam doesn’t even flinch when his brother steps forward and the gun, barrel hot from killing what would have been two witnesses to the bloody tableau in the barn, brushes against his cheek.
Dean kisses the blood from Sam’s mouth and they both forget to worry whether the gun barrel will leave a scar.
that. was. perfect.