Kai is most known for his bighearted, lively brotherliness, making him popular among and respected by other males. Being the eldest son among six siblings, Kai has developed a natural 'big-brother'-like personality, and has a habit of patting everyone on the head. He is naturally welcoming and accepting, although according to Haduki You, he can end up pampering others too much, especially Procellarum's leader Shimotsuki Shun. Kai is known for being a jack-of-all-trades, as well as a very reliable person. Kai aims to become self-reliant, previously living off connections he has made through his part-time jobs and living on his own, prior to taking in Minaduki Rui, who treats as his own son and worries about often. Additionally, Kai enjoys physical activities and work, such as fishing and explorations.