Tisiphone

Tisiphone is one of the three Furies representing avenged murder with Hades being her master.

History
A myth recounts how she fell in love with Cithaeron and caused his death by snakebite. She is also recognized as the furious and cruel guardian of Tartarus.

She was the one who punished the following crimes of murder:
 * parricide (killing a parent or other near relative)
 * fratricide (killing one's brother/sister)
 * homicide (deliberate killing of someone)

The Lightning Thief
She goes onto the bus with two other furies and because of the Mist, people see them as old ladies. Percy sneaks past them using Annabeth's Yankees cap, but they attack Annabeth and Grover while screaming "Where is it?" The group thinks this means Percy, but later they realize the Furies were looking for an it, not a ''he. ''The group think they are talking about the Master Bolt until it is revealed Hades is missing his Helm of Darkness. Later her sisters and she chases them to the beach after escaping the Underworld using Poseidon's Pearls. After Percy's fight with Ares, the Furies realize he is innocent.

The Last Olympian
She is with Hades when Percy and Nicoarrive in the Underworld.