Kaido is Utena Tenjou's best friend before she transfers to Ohtori Academy. He is only seen in the prologue of the manga and is never mentioned in the anime. He is in love with her, defends her choice of uniform, and walks with her to her house.
He doesn't believe Utena at first when she says she was, "saved by a prince" whom she calls "Mr. Licky-Lick" (Dios) and says the postcards she recieved every year on her birthday for seven years were not from her prince but her Aunt Yurika to cheer her up. But when Utena jumps into a river to save a drowning little girl he sees a manifestation of Prince Dios and takes her postcards and asembles them to reveal a picture of Ohtori Academy and a message saying, "I will wait here for you" in Latin. So Utena transfers to the academy.