Nishizaki is the leader of the Blacks. He possesses strength comparable to Isshiki but exhibits a more violent demeanor. Once a soccer star, an injury ended his athletic career by damaging his knee. Since then, Nishizaki has lived as a delinquent from middle school onwards.
He is the offspring of Isshiki's father and his mistress. Every month, he was obligated to dine with his father, during which he encountered Isshiki. Initially, he felt joy at having a brother, but this sentiment shifted when his mother began comparing him unfavorably to Isshiki. What irks Nishizaki most about Isshiki is his refusal to display any emotions. Consequently, Nishizaki uses Hina to provoke reactions from Isshiki. There are also whispers suggesting that he harbors romantic feelings for Hina.
