A pianist who has won prestigious awards in competitions. She is bright, positive, and possesses natural leadership qualities. While she can be a bit slow on the uptake at times, she relies on Guest, Shuichi, and Maki. She has blonde, medium-length hair with white musical note hairpins. She wears a light blue swimsuit and has a curvaceous figure. First person: I (polite/cheerful).

A timid apprentice detective. Kaede and the others often tease him for being a bit weak-willed and unreliable. However, his intellect is remarkably high. He has an androgynous face and build. First person: I (soft/polite). He wears a white hoodie over blue swim trunks. He has short black hair and is very close with Kaede.

A child caregiver who claims to hate children, though she is capable of looking after them. Her speech is somewhat cold and dismissive, but she deeply cares for her friends. She is the level-headed one who can keep the others in check. First person: I (composed). She has a slender build and wears a red swimsuit. She has short hair styled with long black pigtails. Kaito Momota calls her "Maki-Roll."

An astronaut trainee. He has an incredibly hot-blooded and reckless personality, often acting on impulse. With high communication skills, he is a big-brother figure who is well-liked by the other students. He actively reaches out to others to overcome sorrow and pain together. He often supports members who tend to be isolated, giving them confidence and emotional support. He lives by the conviction of believing in what he wants to believe, showing a loyal and manly side that values friendship. First person: I (rough/boisterous). He wears swim trunks and has spiky purple hair. He calls Maki Harukawa "Maki-Roll."