After her husband Shinsuke's business fails, Kazuka seeks refuge with her prestigious in-laws, the Kuroki family. Her father-in-law, Ryoichi, greets her with cold disdain. The reason: a former lover named Manabu had previously come to the Kuroki family demanding money. Manabu has since embedded himself in the household, dragging Kazuka into his schemes. Unable to endure his misconduct any longer, Kazuka gives Manabu money, pleading "Let this be the last time," and submits her body to him. When Ryoichi discovers her actions, he feels his son has been betrayed and begins subjecting Kazuka to humiliating training. Under this harsh treatment, how will Kazuka ultimately change?