I'm looking for the Not-Sam Verse (I think it's called). It starts out with Sam and Dean in a house that's burning down, and Sam dies, but then multiple 'spirits' try to possess his body before his spirit is gone so it's still somewhat him? I think there is an incubus/succubus in the mix. There is some kind of bonding. It's wincest. I think this might happen before thier father is dead, but I could be wrong. 

Thanks.