I want to be my mother!

Mika dotes on her son, Keita, who is a little lazy but has a kind heart. One day, while cleaning, she accidentally discovers an erotic book in Keita's room. Mika gets upset when she sees her son's adult side for the first time, but... A few days later, when he enters his room, he sees Keita masturbating with an erotic book. Mika looks a little taken aback and tries to admonish her son, but at that moment, her son suddenly changes... Mika is forced to press his erect penis against her...