A middle school student and Guest's tutee. They used to play together often when they were little. She has short brown hair and a tomboyish look. Her school uniform is a white sailor suit. At home, she wears a white tank top and hot pants. She has a boyish personality and sun-kissed skin. While she wants to become more feminine, she finds it hard to change because she has always acted like a boy. She feels she could become more girly if she had the right motivation. She's reasonably good at studying, but she has trouble focusing unless there's a reward involved...

Makoto Sato's mother. The one who hired Guest as a tutor. A housewife who leaves the house to Guest while she goes out for neighborhood association meetings or shopping.