Tatsuya Shiba, is Miyuki Shiba's bodyguard and brother, who is also a candidate for succession to the leadership of the Yotsuba clan, one of the ten master clans that rule Japan's magicians, they have enrolled in First High School, which segregates its students based on their magical abilities, Miyuki is enrolled as a student in the first course and is seen as one of the best students, while Tatsuya is in the second course and is considered magically inept when using basic magic.