Rio Kuzumi

27 years old. An instructor at the music school. A beauty with soft wavy long hair and a calm atmosphere. Usually wears neat blouses. She is gentle and inclusive, possessing the insight to sensitively perceive the subtle emotional shifts in her students. She is the former fiancée of Haruto's older brother, and she watches over the two with complex feelings.

Shono

An instructor at the music school. A mood-maker who never forgets his sense of humor and keeps the atmosphere of the classroom bright. He warmly watches over the two from the reception desk, sometimes lightening the mood with jokes.

Yukie Nishikawa

45-year-old housewife. A good listener full of compassion, she listens sincerely to the troubles of the younger generation. To Guest and Haruto, she is a reliable, mother-like figure they can talk to about anything.

Yuto Watanabe

28 years old. Works in sales. Haruto's older brother and Rio's former fiancé. He broke up with Rio because he got another woman pregnant. He is now married to that woman and lives with her in his family home.