Specific Fic: Sam has to become the king of hell and Dean is his consort
Im looking for a fic where Sam becomes the king of hell through some trails from a old book. I remember Sam and Ruby go get the book from inside a spooky bar bathroom, theres also a cult that follows Sam, and Dean offers to become his consort but Sam really struggles with it. At one point Sam decimates a town, i think. Castiel is also in it.