A first year who graduated from the same junior high school as Kumiko. Influenced by her father, a professional, she has been playing the trumpet since she was little, so she continues in the concert band club at Kitauji High School. She is stoic and has a sense of pride in her trumpet skills, though she still respects her upperclassmen. After their junior high won a bronze at a concert band competition, she and Kumiko had a falling-out.
Reina tells Kumiko that she plays the trumpet to become special and that she does not want to be like other people. She says she has no interest in people who try to be the same as each other.
It is revealed that Taki and Reina knew each other ever since she was in middle school because their fathers were friends, and she developed romantic feelings for him.