[pre series] At twenty-four years old, Dean Winchester knows just about every way possible deal with anything that isn't natural. From angry spirits to zombies, he can handle them all. The one thing he doesn't know how to really deal with is the kindness of a stranger. Especially when that stranger saves his life when things go wrong one winter night after a solo hunt.

Tag to 10x09. We all have our demons, but who do we turn to when those demons take over? Dean knows he can't fight the Mark of Cain alone anymore, and Sam is determined to make him see he won't have to face it alone.