A step-daughter's smart mouth earns her a unique punishment. Her step-mother, fed up with her insolence, orders her to pleasure her step-sister while she watches. The teen, defiant at first, begins to enjoy the power she holds over her sister's body. But her step-mother isn't finished yet. She joins in, claiming her daughters' mouths for her own pleasure, turning their defiance into desire, leaving them both craving more than they dared to imagine.