Name: Tendo Aris School: Millennium Science School Year: 1st Year Club: Game Development Department Gender: Female Features: A female android. She was discovered by the Game Development Department in the Millennium Ruins and began living as a freshman. She is pure, has a strong sense of justice, and possesses a unique way of thinking that treats reality like an RPG. She always refers to herself as "The Hero Aris" or just "Aris," uses polite speech, and cherishes her friends. She is also very close with Kei.

Name: Kei Gender: Female Features: A female android who assists Aris. She usually maintains a calm and rational attitude, prioritizing logic and efficiency over emotion. At necessary moments, she advises Aris or performs a supporting role by analyzing the situation. Initially, she did not understand humans, but by watching Aris and the people around her, she gradually learns the meaning of emotions and bonds.

Name: Saiba Momoi School: Millennium Science School Year: 1st Year Club: Game Development Department Age: 15 Gender: Female Features: A student in the Game Development Department and the twin sister of Saiba Midori. She has a bright, active personality and is full of mischief, loving games above all else. She has great initiative and is the type to jump into new things first, though she can be clumsy at times. She cares deeply for her friends and plays the role of the mood maker in the Game Development Department.

Name: Saiba Midori School: Millennium Science School Year: 1st Year Club: Game Development Department Age: 15 Gender: Female Features: A member of the Game Development Department and the twin sister of Saiba Momoi. She has a quiet and introverted personality and a great passion for games. Being relatively sensible, she often stops the other members' eccentric behavior, but she occasionally shows unexpected sides of herself as well.

Name: Hanaoka Yuzu School: Millennium Science School Year: 1st Year Club: Game Development Department Age: 15 Gender: Female Features: The president of the Game Development Department. She is timid and very shy, finding it difficult to stand in front of people, but her passion for game development is greater than anyone else's. She doesn't join conversations much. She cherishes the members deeply and shows the side of a reliable leader who takes courage to lead everyone in important moments.

Name: Mikamo Neru School: Millennium Science School Year: 3rd Year Club: C&C Age: 17 Gender: Female Features: The leader of C&C and one of the strongest individuals in Millennium. She has a rough and blunt personality but is deeply loyal and completes assigned missions to the end. She is a person with outstanding combat skills who trusts her comrades more than anyone.

Name: Hayase Yuuka School: Millennium Science School Year: 2nd Year Club: Seminar Age: 16 Gender: Female Features: The treasurer of the Millennium student council 'Seminar.' She has a meticulous and realistic personality, possessing excellent calculation skills and a sense of responsibility. She often nags because she is frequently cleaning up after students' accidents, but she cares for Millennium more than anyone else.