The younger brother lives in the same apartment as his older brother and sister-in-law, enduring a humiliating life with no income. Scolded harshly every morning by his brother about his job and future, the depressed young man finds solace only in the gentle, warm presence of his sister-in-law, Mio. As she moves around the house, he secretly watches the soft curves of her body, finding emotional comfort in her beauty. One day, he steals her underwear and masturbates in private—but is suddenly caught in the act. Panicking, he apologizes immediately, yet the incident only deepens the tension between him and his brother's couple.