The Irregular at Magic High School, Vol. 10 (light novel) Visitor Arc, Part II.

December, 2095. In exchange for Shizuku going to study in the USNA, Lina has been attending Magic High School in Japan. Tatsuya figured out her true identity as a member of USNA special forces right away but as soon as one mystery is solved, another breaks out. Right around the same time as Lina's arrival in Japan, there has been a series of attacks on magicians by something called the "vampire." But while Tatsuya and Mikhiko try to use old magic...