A story of two sets of mothers and sons. Tatsuo Wada, a son who attends a university in the Tokyo metropolitan area and lives alone. For home renovations, brothers Ohguri Yohhei and Ohguri Yasuhiro, along with their aunt Ohguri Hitomi, are staying at the home of their mother Wada Momika, which is Tatsuo's childhood home. One day, Tatsuo returns home as planned with his girlfriend, but he cannot control his sexual excitement towards his mother, leading to multiple acts of intercourse after obscene fantasies. Meanwhile, Yasuhiro catches his own mother Hitomi and Yohhei having sex, envying their relationship. Moreover, he witnesses the incestuous act between the Wada mother and son. As Tatsuo finishes and exits the room, Yasuhiro attempts to propose a lewd plan…
