According to legend, she was once a Libyan queen (or princess) who fell in love with Zeus. Zeus' jealous wife Hera deformed her into a monster and murdered their offspring. She also made Lamia unable to close her eyes, so that she couldn't find any rest from the obsessing image of her dead children. When Zeus saw what had be done to Lamia, he felt pity for her and gave his former lover a gift: she could remove her eyes, and then put them on again. This way, though sleepless, she could rest from her misfortune. Lamia envied the other mothers and took her vengeance by stealing their children and devouring them.
In Lamia and other Poems (1820), the English poet John Keats writes about Lamia too. In this version, based on the information he found in Anatomy of Melancholy of the 1600s, Lamia has the ability to change herself into a beautiful young woman. Here she assumes a human form to win a man's love.