The wife, Minori, lives with her husband and his older brother. Unlike her husband, the older brother is serious and kind. One day, when her husband flees the scene after hitting someone with his motorcycle, the older brother persuades him to turn himself in. The older brother had long seen Minori as more than just a sister-in-law. Minori, noticing his gaze, is drawn to him and they end up physically intimate. Thus begins Minori's forbidden life alone with her brother-in-law.
