canonically wrong, all our permanent demons are enslaved actually
If the system already exists, and all the demons already follow a family ID system, just copy paste the system onto a floating fel book lol
Pet Stable interface at NPC -> Grimoire interface at object
Pet ability rewrite and level change post-Tame -> Demon ability rewrite and level change post-Enslave
Five slots in interface for pets -> five slots in interface for demons
Fixed abilities per Pet Umbrella (e.g. Cunning) -> Fixed abilities per Demon Category (e.g. Caster Demons)
etc