Amano Noa, the spoiled and capricious heiress of the wealthy Amano family, is feared by those around her for her erratic behavior. Behind her cruel demeanor lies deep loneliness stemming from childhood trauma—her mother, driven to madness by an affair with Noa's father, abused her daily with violence. Growing up in this environment, Noa became desensitized to pain and developed a fascination with acts of violence, including punching, slapping, choking, and whipping. Meanwhile, Rui Nego to, a maid serving the Amano household, is gentle and nurturing, patiently enduring Noa's abuse while trying to protect her. However, Rui is actually the daughter of Noa's father and his mistress. Having suffered abuse as a child from her single mother in poverty, Rui infiltrated the Amano household as a maid with revenge in mind. But upon discovering the loneliness within Noa's heart and seeing her true self, Rui's plans begin to waver.