His mother, Itsuki, was shocked and depressed after recently getting divorced due to her father's affair. Worried about his mother, her only son, Ataru, accidentally sees his mother masturbating. Touched by his son's kindness, the loneliness he had been holding back until now suddenly overflows, and he asks his son to comfort him. Although confused, the son accepts his mother and gradually begins to be attracted to her, and they cannot help but desire each other...