When the older sister finds out that her younger brother is molesting her and taking secret photos, she tells him to stop by touching her body, and they decide to ride the train and bus together. At first, he just touches her, but before long, he can't hold back and his hand goes inside her underwear. The younger brother gets more excited as his sister tries to keep her voice down so that others don't notice, and when he pulls out his dick, the older sister is hesitant but reaches out for her brother.