The protagonist of this story, Yasuhiro, is currently a hikikomori. The event that triggered this was his parents' marital argument. His selfish and unfaithful father and his beloved mother, Shoda Chisato, were being assaulted by his father one-sidedly right before his eyes. Then, he desperately hugged and defended his mother who was about to cry. However, in this situation, his crotch was inexplicably erect. And he started to become aware of his own mother as a woman. Wasn't he becoming like his father, who couldn't help but cheat on every woman he saw...? Then, one day around three months into his hikikomori state...
