Brother and sister Tatsuya and Miyuki Shiba have enrolled at the National Magic University Affiliated First High School. Miyuki will be starting as an elite Course 1 student whereas Tatsuya, because he’s stricken by a certain deficiency, will be a Course 2 student as an “irregular.” Admired by her fellow students, Miyuki worships only Tatsuya, causing him to draw the ire of the Course 1 students.