After divorcing due to her husband's infidelity, Mariko lives alone with her son, who is currently job hunting. Worried about her son's future while striving to become his emotional and financial support, she finds hope in his encouraging words: "I'm going to get into a top-tier adult video company and make life easier for you, Mom!" Despite her optimism, Mariko remains deeply concerned about her son's loneliness. As he approaches adulthood with no girlfriend in sight, her maternal concern gradually shifts into emotional intimacy. One day, exhausted from studying, her son begins dreaming about his mother masturbating and starts fantasizing about having sex with her. Slowly, love and mutual desire intertwine between mother and son, drawing them closer to the forbidden garden of incest.