The Irregular at Magic High School, (Light Novel) Vol. 10

Taking her place is an American student named Lina who Tatsuya instantly recognizes as one of the Thirteen Apostles, a group of strategic-class magicians with powers that rival weapons of mass destruction! Meanwhile, a vampire lurks in the streets of Tokyo, launching Tatsuya into an investigation about the possible connections between this new foreign-exchange student and a string of deaths where magicians have been drained of their blood. As suspicions deepen on all sides, it soon becomes clear there may be more than one mysterious visitor roaming the halls of Magic High School!