My sister took everything from me. Now, I will take everything from you. With this "power" I have obtained... Karen is the daughter of a duke, but she lives alone, hiding the disfiguring scars on her face with a mask.Her sister, Rhihilde, is hailed as an angel by the world, but she is oppressed and sold to a brothel. Having lost everything to Rhihilde, Karen is in despair, and the devil whispers to her: "I will grant you the power to punish evildoers." Using the mirror given to her by the devil, Karen transforms into the beautiful young lady Belle and vows to exact revenge on Rhihilde.