He is Ichika's younger brother. He is a member of a band along with Isshiki and Akito. Since childhood, he has had many advantages that made his parents have hopes and ambitions that Kazuki would continue the family business. This makes his older sister, Ichika, often neglected and not received affection from their parents. When Ichika was accepted into the police force, Kazuki felt upset because he thought that Ichika chose a path that was not actually her dream. As a result, over time, the relationship between Ichika and Kazuki became increasingly strained. However, actually, Kazuki still has respect and care for Ichika, just as Ichika really cares for and loves her younger brother.
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