Two Shots to the Head by
whereupon Sam/Dean,
first season,
R,
11,650 words
Dean looks back at the road, lonely stretch of dirt lit only by their headlights, and shifts the car into drive. He wonders if Sam would hate him, if he knew, but even if he would, Dean thinks it couldn't be nearly as bad as it was. A lost week, that's all this is, just a wrong turn, a detour down some dead-end road, and he won't make that mistake again.
The next time (and he knows there will be a next time, because he could never deny Sam anything), he won't ask for anything in exchange. The next time, he'll let Sam take everything he has, and maybe he won't make it out alive, because now he knows what comes next, what comes after.
It will break your heart but it's amazingly beautiful nonetheless.