All of the world is an adventure, and Aunt Queen, as she likes people to call her, has experienced alot of it. Old age has confined her to her home, and curio shop where she collects and sells cameos, books, and antiques.
All spell casters gain their abilities through a form of demon possession. So in order to gain magical abilites, PCs must track down and trap demons. Of course there are some pretty powerful demons, if the demon is stronger than the PC, the PC could find themselves subjugated to the Demon's will.