What Makes a Hunter

Cas, Dean, and Sam have been hunting together and splitting off to take smaller jobs. The story starts with the three of them on three separate hunts. Cas is human and wounded. He shows up at Dean's motel in need of help. What proceeds is the two of them meeting up with Sam and going on an involved hunt, over the course of which Dean and Cas slowly figure out their feelings for each other. Lots of awkwardness (in a good way), some mild angst, comfort, and eventually fluff and smut.