Backlash table for Fin:
2: Possession: He must make a Spirit roll at -2 or become possessed by a demon. Possession entails the demon have complete control over you unless an exorcism is preformed. Every minute you have a chance to escape. If you succeed at a spirit roll at a -4.If he manages to stave off the possession he must find a new demon to get power from.
3: A portal to hell opens and a number of lesser demons = to the amount of power points borrowed are released.
4-5: A medium blast template around him does 4d6 damage to friendly creatures, and him.
6-8:Takes a wound and the power used is controlled by the demon.
12:same and the Fin gains favor with the Demon.