Seventeen-year-old blue-haired Karou finds herself at the center of a battle between supernatural forces and comes face-to-face with the truth about angels and demons.

Bickering New York City roommates and high school seniors Meg and Shar must find a way to balance their love of fashion with the drudgery of being special-assignment Sirens, luring to the Underworld those whose unholy contracts are up.