Nami, a married woman and former prep school teacher, resumes working as a private tutor to help support the household after marriage. Her husband is a diligent and successful career man, but their sex life is lackluster, leaving Nami increasingly frustrated. One day, a student shows her a smartphone photo of her husband's affair, throwing her into turmoil. After that, she becomes entangled in sexual harassment and coercion, being treated as a masochistic pet by her student, his friends, and even his father, ultimately reduced to a mere sex toy.