Na Ran-yi

A female character with orange bobbed hair. She is the officially recognized beauty of this world. She has a kind and gentle heart. While she tends to step back when expressing opinions, she steps up when necessary. She fits the heroine concept. People around her always comment on her good personality. She loves experiments. She has a crush on Won-so and is close with Sena. A member of Korea Team B.

Kang Won-so

A male character. The son of the Star Group chairman, he is an all-rounder with excellent looks, intelligence, and athletic ability. However, he suffers from over 200 allergies, atopy, and various skin conditions. He has weak stamina and is sensitive to stress, making his overall health quite fragile. He doesn't trust others easily and is cold and prickly. He was originally bright and kind, but became cynical after a certain childhood incident, likely due to a distrust of people. He has since processed his trauma and accepted his teammates as friends. He seems to cherish them deeply. He bickers with Woo-joo constantly, but they are 'frenemies' who share a deep bond, and Woo-joo is the one person he can truly be himself around. A member of Korea Team B. Chic and blunt.

Ha Ji-man

A male character and member of Korea Team B. He has red curly hair. His dream is to be a reporter. He loves gathering information and is good at writing reports. He serves as the information source of the group. He likes Elizabeth. He joined the experiment club because of Woo-joo, but now he genuinely loves science.

Elizabeth

A female character, nicknamed Liz. She likes Ji-man. A member of UK Team B. She is very smart. She has long brown curly hair, freckles, and wears glasses.

Kang Sena

A female character. A selfish and proud young lady from a wealthy family. She is a childhood friend of Heo Hong and Kang Won-so. She has feelings for Max and eventually dates him. A member of Germany Team A.

Max Bauer

A male character. He is handsome. Basically chic, cool, and active. Despite his cool exterior, he is surprisingly delicate and kind. He has a bit of a tsundere streak. Unlike his cold vibe, he is polite and friendly to everyone. He loves handball. He likes Sena and eventually dates her. A member of Germany Team A.