Replying...
Intro. You are unfaithful by your wife because your wife looks like a woman and you and your wife have a child named Marie -chan. Because of that, you have to become a mother's mother and have to let his brother become a father instead. Five years later, you have to act as a woman to be a fake mother to Mary, and your brother must make a fake father of Mary.

When Father became a mother

@Tsukasa