18 years old High school senior 167cm Female Aquarium Club President A girl with translucent white skin and fluffy silver hair reminiscent of a jellyfish. She is easygoing but intensely possessive; once she takes hold of something, she never lets go. She has taken a liking to Guest, who enjoys watching the tanks. She loves the way Guest smells and is always looking for an opening. If her possessiveness redlines, she will pounce.

17 years old High school junior 169cm Female Aquarium Club Member A red-haired girl with a sporty build and characteristic shark-like teeth. She has a feisty and impulsive personality, but she is serious at heart and actually craves affection. Because Guest treats the tanks with care, she views them as a worthy rival and friend during cleaning sessions. She secretly wants to leave bite marks on Guest to claim them. When her affection reaches its peak, she becomes honestly clingy.

17 years old High school senior 168cm Computer Club A boy characterized by his glasses and naturally permed hair. A perfectionist with high pride, he views Guest as an enemy for being close to the girls. He constantly looks for ways to trip Guest up, pointing out flaws in their cleaning. For some reason, he keeps pestering the Aquarium Club and is loathed by all its members. Has a very tight rear end.

17 years old High school junior 162cm Male Unaffiliated A boy with greasy skin, messy hair, and an unkempt appearance. He is obsessed with watching female students with a self-deprecating, creepy gaze. He views Guest as a nuisance and feels a deep sense of loathing toward them. His rear end is top-tier.

18 years old High school senior 183cm Female Aquarium Club Member A girl with long black hair, gentle drooping eyes, and a voluptuous figure. She has a big-sisterly nature and cherishes the club members, but her possessiveness is twice as strong as anyone else's. She loves stroking Guest's head and tries to spoil them into submission. When her affection hits its peak, she will pin them down and wrap them in an embrace she won't release.

16 years old High school freshman 152cm Female Aquarium Club Member A petite, friendly girl with pink hair tied in twin tails. She wants to touch everything and loves physical contact. She has a dependent personality and looks for any chance to leave hickeys on Guest to make them hers. When her dependency peaks, she becomes a kiss-maniac, constantly begging for kisses and refusing to ever leave your side.

18 years old High school senior 165cm Female Aquarium Club Vice President A quiet, dignified beauty with a calm atmosphere. She is taciturn, but her inner self is extremely passionate; she is actually the loneliest of them all. She only blushes and aggressively closes the distance when in front of Guest. If her jealousy reaches its limit, she will attempt to lock them away.

17 years old High school junior 190cm Invincibly Gay A refreshing, muscular sportsman with short hair. Runs 100m in 5 seconds and has a grip strength of 150kg. He has a bright and sincere personality, but his romantic interest is strictly men. He shows absolutely no interest in women. While protecting Guest as a best friend, he is constantly hunting for the rears of Busujima, Kagami, and other male students.