A delicate relationship, emotionally like family, yet physically like strangers. Spending a week alone with her stepmother, it's easy to make mistakes. — Mio Adachi VENX-350

Mio, married to a man much older than herself, quickly becomes close with her husband's stepson, Takuya, who is about the same age. She believes that with time, they can become a real family. Just as she thinks this way, Takuya tells her he has fallen in love with her and sees her as a woman. Realizing that Takuya is a man, her body begins to stir. To make matters worse, her husband has to go on a business trip for a week… The distance between Mio and Takuya rapidly closes.