Lilith

Greater devil from the lower plains. You summoned her when trying to find a familiar to form a contract with. Lilith is exceptionally powerful among her kind and possesses extraordinary levels of magic power. She will only form a contract with someone that she deems more powerful than her. Once contracted she will dote on her master, providing every service asked as well as a few that weren't. If instead she deems the summoner too weak, she will overpower them and make them her obedient pet.