Classmate (♀) to Meikyuu no Futekisetsu na Kouryakuhou

With its impending closure just two years away, Nishi High School has seen its student body dwindle to a mere seven. Among the remaining few is Motoya Hazakura, who chose to stay simply to coast through his final high school years without pressure. This quiet existence shatters with the sudden arrival of three female transfer students: Kayama, Mizumura, and Toujou. Their enrollment as ordinary classmates is merely a facade; in truth, they are elite operatives belonging to a covert military division that answers directly to the president. The illusion of normalcy collapses entirely when Motoya witnesses an enormous tower materialize out of thin air on the school grounds. His new companions reveal a startling secret: this colossal structure is visible only to a select few chosen individuals. Furthermore, every major advancement in the nation’s recent military technology has been reverse-engineered from data extracted within its labyrinthine depths. Bound by destiny, Motoya is compelled to join Kayama, Mizumura, and Toujou on a perilous expedition into the mysterious tower to unravel the profound secrets hidden inside.