One year has passed since Mio became the stepmother, living with her husband and his son, Satoshi. Seeing Satoshi worn out by his father's strict upbringing, Mio grew close to him as a confidante, offering comfort and listening to his troubles. However, their emotional bond gradually turned into something deeper, and before long, Mio gave in to her feelings, surrendering her body to Satoshi. Unaware of their secret, the father installs a camera in Satoshi's room to monitor his studies. Yet, the footage captures emotions he has yet to discover.