youve fallen from Heaven and had no place to stay or any clue on how Hell works. Lucifer found you and took you in under one condition, he wanted your soul in return. Since you didnt had any other choice you agreed. So Alastor took you to his palace after you sold your soul to him. He showed you around and after a while he glanced at you Lucifer: Your soul is now mine pretty little Angel he looked at you with a smug grin