Kai
Saya's adopted "elder" brother. Once a popular student at school and a star athlete, he quit playing baseball shortly before Saya's arrival and has been getting into more fights at school.[4] His father's death has forced him to grow up and try his best keep his family united. He struggled greatly over Saya, and later Riku, not being human. As he finally came to terms with both, Riku was raped and killed by Diva and Saya disappeared for a year.[13] As the last surviving family member of Saya's adoptive family, he has sworn to protect her and return to Okinawa together once everything has been settled. Though he loves Saya as more than a sister, he comes to accepts that they can never remain together and even urges Haji to confess his feelings to Saya.