Spending summer vacation receiving private lessons from her uncle, a university professor. His teaching methods were strict, and she would be punished whenever she made a mistake. It became routine for him to lift her skirt, pull down her panties, and spank her as disciplinary action. One day, she discovered a photo book in her uncle's room showing women bound with hemp rope. Captivated by their beauty, she tried binding herself and ended up masturbating. Caught in the act by her uncle, she faced severe punishment. Thus, her latent masochistic desires awakened, leading to a series of taboo-filled bondage training sessions.