"You use the masturbator too much." Chitose tells her son, who is worried about not being able to ejaculate during sex with his girlfriend. Even though he is still at an age where he wants to have fun, he has become so used to high-performance masturbators that he can no longer feel vaginal pressure. What will happen to him in the future?! Worried as a mother, Chitose decides to use her own lewd body to get her son used to the stimulation of a woman's body, but... Her tight pussy is so much tighter than her son could ever imagine, and his insensitive penis begins to get hard in an instant!