Furies

In Greek mythology the Furies were underworld deities concerned with punishing mortals who committed severe infringements of both mortal and divine law - they were especially prone to attack those who committed the act of hubris (an act in ancient Greece that was akin to sacrilege or defilement).

The Furies were envisioned as frightenin beings that were an embodiment of vengeance, once they sought out a mortal they would hound them without mercy and were somewhat similiar to demons of other mythologies - however unlike demons the Furies were not enemies to the gods.

The Furies are the basis for the modern word "fury" and "furious" which is to be consumed with great and often uncontrollable anger.