[Silent, weak-willed, gloomy girls are creatures who can't talk to anyone] Sakura, who has a large chest and is troubled by stiff shoulders, is introduced to a personal gym run by her father's friend for exercise therapy. She is shy, but when she hears that it is one-on-one instruction, she starts attending with peace of mind, her body condition improves, and her parents are grateful to the teacher and trust him, entrusting their daughter to him. Meanwhile, the touching of her body becomes more intense day by day, and she is threatened with insidious threats, and she is in a situation where she cannot escape, and the pranks escalate...