Masato, who lost his mother at an early age, did household chores between schools and lived with his father on a three-legged race. My father brought his remarriage partner, Yuri, at the end of the summer when Masato was about to take the exam. For Masato, who grew up in a man's family, life with Yuri was embarrassing and a series of embarrassments. Its smell, gestures, gentle voice, soft breasts. It was inevitable that a young boy who had just entered adolescence would suddenly appear and be aware of his young mother-in-law as a woman.