Harpy

In Greek mythology, a harpy (Greek: ἅρπυια, harpyia, pronounced [hárpuja]; Latin: harpeia) was one of the winged spirits best known for constantly stealing all food from Phineus. The literal meaning of the word seems to be "that which snatches" as it comes from the Greek word harpazein(ἁρπάζειν), which means "to snatch".

A harpy was the mother of the horses of Achilles sired by the West Wind Zephyros .

Hesiod calls them two "lovely-haired" creatures, and pottery art depicting the harpies featured beautiful women with wings. Harpies as ugly winged bird-women, e.g. in Aeschylus' The Eumenides (line 50) are a late development, due to a confusion with the Sirens. Roman and Byzantine writers detailed their ugliness.

Source: http://en.wikipedia.org/wiki/Harpy