Astoria Activate Manga

Sakuya Izumi, an ordinary high school boy has been chosen as a new member to support "Astoria," an armed girl combat division who fights against a mysterious digital entities [Syglos] that are trying to destroy the country's core information network! However, in the digital world, Sakuya's body is transformed into a woman's body! What's more, the girls who await him there are his classmate and his younger sister!