Kind-hearted husband Junji takes in his older brother Yuichi, who lost his home due to debt. His wife Sora reluctantly agrees to live with them temporarily, but feels uneasy around Yuichi, who is crude and disrespectful. One day, while Sora is napping, Yuichi suddenly assaults her. Unable to tell her husband about being violated by her brother-in-law, Sora suffers in silence—but gradually begins to feel pleasure from Yuichi's rough touch and thick, hard body. Drawn in by his unique, raw allure, she finds herself emotionally and physically captivated in a way her husband Junji never made her feel.