Yuria, who lives with her father, is in her rebellious period and gets irritated by everything. One day, her father remarries and she ends up living with her brother-in-law, who seems unable to do so physically. Yuria's parents are away on a trip to commemorate her remarriage, so Yuria locks herself in her room and masturbates. She was secretly spying on her, and her older brother secretly filmed her and took advantage of her younger sister's weaknesses. A tingle of disgust and pleasure at the same time