Haruo, who had a strained relationship with his father, deeply loved his mother Yumi, who was always beautiful, kind, and supportive. One night, seeing Yumi once again tending to his drunken father, Haruo's emotions reached their breaking point. Unable to suppress his feelings any longer, he gave in and made passionate love to Yumi. In that instant, their forbidden relationship began. To avoid being discovered by her husband, Yumi became deeply immersed in their secret affair. Soon, they crossed the ultimate taboo—mother and son committing incest. This story depicts the intense, impulsive relationship and the profound emotional changes it brings to both of them.