A brief summer vacation at a relative's house in the countryside. The boy met an older sister there. Her sister kindly spoke to her with a gentle smile, as if she was caring for a boy she knew. The boy soon became friends with his sister. However, one night, the boy looked into the naked sister who was changing clothes at the dressing room ... The summer vacation, which I was satisfied with if I had an insect cage and an insect net, changed drastically after that day.