Azazel/YED reincarnation
So I read a story on SPN fanfiction many years ago. It was written from Azazel point of view. How he is reincarnated after his death. He has some interest in Dean. Sam gets taken by some creatures underground and dean is drinking a lot. SO Azazel goes and offers him help. There is a scene where they are in a high rise apartment, and they get attacked at night and Dean is hanging from a ledge of a window. In the end Azazel sacrifices himself.