Expanding Earth

“Where is Saitama…?” Japan was divided due to the expansion of Earth. Monsters and new continents that suddenly appeared. In order to cultivate the new Earth, the Tokyo Metropolitan Government has decided to send first-class pioneers, known as human weapons, to unexplored areas. Kuroki, who was unable to become a first-class pioneer, gets involved in an incident with his partner, a first-class pioneer rank 8!