Kanojo ga Onii-chan ni Nattara Shitai 10 no Koto

Nanase begins high school by moving into a shared house with a unique rule assigning each resident a family role. Maki, a 20-year-old female police officer, is designated as the father. Tsugumi, a 10-year-old elementary student, takes on the role of mother. Nanase, a 15-year-old high school student, is assigned as the brother, while Karin, a 13-year-old junior high student, is the sister. The story explores how Nanase navigates life with this unusual group.