Hayato Matsuzaka is a non-powered human. His wife is Aoyun Endesaen, his child is Dione Matsuzaka, his grandchild is Haneul Black, his great grandchild is Misaki Black, and his great-great grandchildren are Takeshi and Kiyoko Kim.

Hayato Park (portrayed by Sota Fukushi) is one of Cass' friends. He is and is a Caste 2 private school student/athlete.