Title: Monsters of Men
Rating: NC-17
Genre: AU, Demon!Dean
Pairing: Dean/Castiel
Spoilers: None
Word Count for Chapter: 4,877
Summary: Even if he has an angel he's supposed to be taking care of, Dean still has a job to do. But Castiel is chatty and nosy, and Dean is starting to regret bringing him along for a hunt.

Read it at Ao3