Sam | Lucifer
I'd much rather break them in ways that don't involve dying, but every once in a while it's worth it.
Probably a lot of the details are the same. He killed his brother. Except, he did it because Abel had been corrupted by you, and he was going to go to hell. Instead, Cain made a deal to go to hell himself for killing him, and Abel's soul ended up in Heaven. Cain became a demon, one of the immortal knights of hell.