GATE - Jieitai Kanochi nite, Kaku Tatakaeri

In the 21st century, a gate suddenly appears in Tokyo's Ginza district. Through it pour monsters, knights akin to those of medieval Europe, and other fantasy-like beings. They kill many of the city's citizens, a catastrophe that becomes known as the Ginza Incident. In response, the Japanese government sends a small group of soldiers from the Japanese Self-Defense Forces beyond the gate into the alternate world on the other side. Led by Youji, an otaku soldier, the unit learns that villages in this world are under attack by a dragon. As they travel through the dangerous new land, an elf girl who survived the dragon's rampage joins their group. Together they navigate a realm where fantasy and military reality collide, confronting the aftermath of the dragon's violence while carrying out their mission in an unfamiliar and hostile territory.