义mother's sanka prequel!

Tomonori, who was living an ordinary school life, lost his mother to illness, but his father, Seiichi, soon remarried a beautiful woman, Hanae. She and her stepchild ``Marie'' were living a reasonably happy life together. One day, he learns that Seiichi has been having an affair with his current stepmother, Hanae, for many years. On a night alone together, Tomonori attacks his stepmother Hanae. Please stop, Tomonori-san... When Hanae's nightgown was torn from top to bottom, Hanae's bewitching body was exposed. As a result of this, his feelings for his beautiful mother-in-law became distorted, and his days of revenge began.