Shūichi Kushimori (Kazunari Ninomiya) lives with this mother Yūko (Kumiko Akiyoshi) and younger stepsister Haruka (Anne Suzuki). One day, his estranged stepfather Ryūji Sone (Kansai Yamamoto) suddenly returns home and begins to freeload off his family. After Shūichi encounters what appeared to be Sone making sexual advances towards Haruka one night, he tries to get rid of Sone. However, Shūichi discovers that it is impossible to do so legally as Haruka is his daughter, and Yūko asks him to endure it until Haruka turns fifteen and can choose Yūko as her legal guardian.