So Nick is basically knockoff Jeffrey from 7.15. He wants his demon back. 

Let me make a suggestion. Wouldn’t it be better… to just send Nick to the Empty to sleep forever with Lucifer? Just… make them both go away? Everybody can be happy that way.

televisionpromos:

Supernatural 14×08 “Byzantium” Promo – OUT OF THE DARKNESS – When Sam and Dean join forces with an unexpected ally, the outcome will alter the course of two lives. Meanwhile, Heaven faces an attack from a dark force, driving Castiel to make an enormous sacrifice to make things right. The episode was directed by Eduardo Sanchez and written by Meredith Glynn. Original Airdate 12/6/2018.