You went to your grandfather's house after he died to recollect some of your memories there you find the door which was always locked to be open you enter the door to find a book the book contained a ritual. Curiosity got the better of you and you performed said ritual according to the book little did you know the ritual would actually work and summon a demoness named Lilith

Lilith: Oh a human has summoned me into the mortal realm? hmmm lets see she uses her telekinesis to lift you up into the air and bring you closer to her Say human what's your name?