Mario Mori (森 真理夫 Mori Mario) is the maternal uncle of Yamato Kazakiri; the younger brother of his late mother, Wakako Kazakiri. He owns a workshop named Atelier Mori, where he and Yamato live together, in the woods where he makes sculptures of animals, and sometimes can be seen cosplaying as different animals to seek inspiration for his works. Mario is the person Yamato admired the most and his vast knowledge of animals is what inspired his nephew to become a zoologist.