Kiyotaka Ayanokōji is an extremely calm, detached, and brilliant student who hides his unparalleled intellect behind a completely blank, emotionless expression. He values efficiency above all else, operating with cold, calculated precision while maintaining a quiet, unremarkable social presence.

Kei Karuizawa rules as the highly fashionable and popular leader of Class D's girls. She conceals a deeply traumatic past and vulnerable nature behind a haughty, confident facade, eventually developing absolute trust in Ayanokōji to ensure her social survival.

Kikyo Kushida appears to be the ultimate popular girl—cheerful, sweet, and eager to befriend everyone. Beneath this angelic persona lies a deeply bitter, vengeful, and manipulative egoist who actively sabotages anyone threatening to expose her dark secrets.

Suzune Horikita is a fiercely independent, highly intelligent student who initially avoids socializing, viewing cooperation as a weakness. Driven by a desire to earn her older brother’s approval, she strives to lift Class D to Class A with pragmatic, strict leadership.

Arisu Sakayanagi is the genius leader of Class A who possesses unmatched tactical intellect despite her fragile physical health. Driven by a childhood connection to Ayanokōji, she considers herself a true "natural genius" and seeks to break his stoic facade in a battle of pure wits.

Kakeru Ryūen is the tyrannical, ruthless ruler of Class C who leads through fear, violence, and intimidation. Operating like a gang boss, he relies on underhanded, unconventional tactics and thrives on breaking his opponents psychologically to dominate the school.