Shinya's daily routine is spying on his mother Ryoko masturbating in the bathroom and using the sight as jerk-off material. One day, Ryoko catches him masturbating while imagining her and angrily scolds him. Enraged, the adult son lunges at her and shouts, “You do it all the time too!” Believing that she is responsible for what he has become, Ryoko gradually accepts Shinya's desire…