My favorite demons are Beelzebub and Satan. I have figures of both to repel succubi that threaten me on my path to wizardry. Other favorite demons would be Barong, Seth, Alice, and Quetzalcoatl.
In terms of games, I'm basically a Nocturne baby. I also played through 4, part of 4A, Devil Survivor 1, Persona 3 FES, Persona 4 the Golden, and Persona 5 (vanilla) plus some irrelevant Persona spin-offs. I also played the start of the Persona 1 PSP remake, but stopped because I hated the combat. I decided not to give Atlus my business for Persona 5R because they cucked to the sodomites. If we count Persona games, my favorite spin-off is P3 FES. If we don't, it's Devil Survivor 1.