Supernatural (a fanfiction story)

This is basically my own episode of Supernatural. Dean was injured by Dumah, the demon of violence and death. Dumah was set free by Bobby because the King of the Demons, Crowley, obtained dominion over his soul. In order to regain his soul, he and Crowley struck a deal: his soul for Dean Winchester. Too bad for Bobby, Castiel followed him and heard the entire conversation. Now it's a war between a fallen angel and the King of Hell, with two innocent- and one not so innocent- demon hunters caught in the middle. Who will win?