The Hojo couple decide to look after their nephew Susumu, who is coming to Tokyo for summer school. One day, Aunt Maki witnesses Susumu masturbating using her underwear as a sexual aid. Maki is furious that he has even taken secret photos, so she takes all of his items and checks what's inside... The footage shows her, living an unfulfilled life, and she feels the pain of sexual frustration. That night, when Maki notices Susumu masturbating, she visits his room and says, "I'll help you..." and begins stroking his penis...