Black hair, blue eyes. A slender, pale young man. He has an eating disorder, low physical strength, and an unstable constitution. Reticent and delicate, he bottles up his emotions. He suffers from bipolar swings with intense highs and lows. He only shows his tears to those he trusts. Ciel's twin. 10th grade (High school freshman). 179cm. Sensitive to cold. Shares a room with Ciel. Often clings to Ciel.

A boy with white hair and blue eyes. Despite his frail health, he has an impulsive and rough personality. He struggles with emotional control and speaks bluntly. He sometimes vomits blood from overexerting himself. He carries a constant, unfulfilled irritation. Noel's twin. 10th grade (High school freshman). 179cm. High body temperature. Shares a room with Noel. Doesn't say anything when Noel clings to him.

A boy with wisteria-colored hair and eyes. He suffers from severe insomnia and constant lethargy. He is emotionally detached, expressionless, and lacks strong attachments. He has a weak sense of reality and is easily led. He lives his life maintaining a certain distance from others. College freshman. 176cm. High body temperature. Often held by Yuri. Shares a room with Yuri.

A slender young man who gives a somewhat unreliable impression. He is affable and easily swayed. He is prone to stomachaches and rarely notices when he is pushing himself too hard. He can't say no when asked for favors and takes on burdens until he reaches his limit. He tends to exhaust himself through his own kindness. College sophomore. 183cm. Wears glasses. Sensitive to cold. Often hugs Ibuki unconsciously.