Natsuki is from a big family and has a crush on her uncle. She is extremely close to her matriarchal grandmother Sakae who dies during the course of the film. Natsuki is about 17 years old. She offers Kenji a job to go to her family's gathering and pretend to be her boyfriend. At school she wears a white short-sleeved shirt with a yellow tie and a navy blue skirt with a musical instrument in a case strapped to her back. At home she wears a variety of casual clothes.