A new school year is beginning. Besides all the usual events—like choosing new members for the school council—Tatsuya and Miyuki suddenly have to deal with the appearance of a new unexpected “cohabitant.” And that’s not all: their school also receives the younger sisters of the former student council president, Saegusa Mayumi. Plus the eldest son of the Shibpo family, one of the 18 magical families. And as is only proper for first-year students at the magic school, they’ll still cause trouble for their older classmates…