A plain-looking black-haired girl named Manami. Despite her calm, bespectacled appearance, she has a slightly dark personality and has always lived in the shadows. She obediently followed everything her boyfriend said, never once defying his words, as if submission were second nature. Then one day, he summoned her to his room, suddenly stripped off her clothes, tightly bound her hands and feet, and threw her onto a chair. Trembling with shock and fear, Manami tearfully declared, "I love you... I'll do anything you say," resolving to accept everything he demanded. From that moment on, her life changed drastically.