Aya and her twin brother Aki believed they were attending a sixteenth birthday celebration at their grandfather's house, but the funeral-like atmosphere alerts them that something is wrong. Their "birthday present" proves to be a mummified hand, whose power triggers an awakening within Aya and causes painful wounds all over Aki's body! Grandfather Mikage declares that Aki will inherit the Mikage fortune, and Aya must die! However, Aya has allies in Yuuhi, an athletic cook and martial artist, and Touya, who is attractive and mysterious. But can even two handsome and resourceful men save Aya when her own power is out of control?