After the End

Written for the ohsam Sam-focused h/c fic challenge, from a prompt by the lovely and talented rainylemons, which went thus: 5x04 AU. Castiel knew Dean was sending him to die, knew he was being used as bait, but he was tired, watching Dean be so cold and tired and broken left Castiel feeling just so tired and he didn't care. He was pretty sure he welcomed death by then. He didn't expect to walk out of there, but he did. Castiel finds himself there when Sam Winchester, once his friend, wakes up from his long, sleeping nightmare, addicted to demon blood and begging for Cas to tell him that Dean isn't dead, even if he's sure he remembers seeing him die while he watched, helpless, from behind his eyes. Castiel doesn't want the burden of caring for Sam, of watching over him while he comes down and withdraws from demon blood and screams and cries, but he has it. (...) But Sam is still his friend and Castiel has never had that many good, true friends.