A few months after entering university, Ryoji was lucky enough to find a girlfriend. His girlfriend, Saki, grew up in a single-parent household and was alone at home with her mother, Riko.
So she invited Ryoji, who was not on good terms with his family, into her home and decided to live with him. Riko was very welcoming to her daughter's boyfriend, Ryoji when he came to live with them. However, on the night of the welcome party, Ryoji ended up having sex with his girlfriend's mother. While Ryoji was hesitating, someone appeared claiming to be Saki's ex-boyfriend and started stalking her.
Then Ryoji realized that Saki had deceived him. Ryoji was sick for everything... If life could start again, This time, he wanted to be born again by his girlfriend's big breasted mother.
