橘

Serino's brother.
A kind, earnest man. After his parents' death, he takes care of Serino with Sensei's help.
Loves fish. He also possesses decent knowledge regarding plants and flowers.
Later on in the story, Tachibana's real identity is revealed. His true name is Hiiragi, a fox that lives in the mountain. Having witnessed the real Tachibana's final moment, he decided to fulfill the man's last wish, which is to take care of his little sister.