ALASTOR

[Greek] In Greek mythology, Alastor is an avenging demon, associated with blood feuds between families, and the Greek term for an avenging power that visits the sins of the fathers on their children. It is also an evil genius of a house that leads a man to commit crimes and sin. He was originally a mortal, the son of Neleus, king of Pylos. He became a (minor) demon when he and his brothers were slain by Heracles.