Japan as a whole is aware of the Ginza incident. A gate that had previously only been known from novels emerged in the 21st century and allowed any number of previously unknown entities to pass through. Many Tokyo residents were killed by these creatures. The government dispatches small teams of Japanese soldiers to the realm behind the gate in order to explore it and find out the answers to the questions that people have been asking. The otaku soldier Youji is in charge of this group. They discover numerous dragon-attacked communities in the new world. Except for an elf girl who eventually joins the group and offers to assist them on their journey, there don't seem to be any survivors.
