Classmate (♀) to Meikyuu no Futekisetsu na Kouryakuhou

Nishi High School is set to close in two years, and its student body has dwindled to seven students, including Hazakura Motoya, who remain for the final free year of schooling. Three new female transfer students—Kayama, Mizumura, and Toujou—arrive unexpectedly. They are part of a military unit operating under the president’s direct command. Shortly after their arrival, a massive tower appears on the school grounds. Only a select few can see it, and the country’s recent military advancements are said to stem from data collected within. Motoya is selected to enter the tower with the three girls to investigate its secrets.