Thrown into an unfamiliar world with just fragmentary memories and their names, a group of strangers can only feel fear, survival, and instinct. They're left with no other option but to undertake the job of soldiers in the Reserve Army in Grimgar, a world that resembles a game. Their duty is to eradicate any threats to the peace of their new home. However, the ones who didn't make the cut must band together to form a party and stay alive: Manato, a priest with a magnetic personality; Haruhiro, an anxious thief; Yume, a lively hunter; Shihoru, a bashful mage; Moguzo, a gentle warrior; and Ranta, a boisterous dark knight. The game-like world they're in is anything but; there are no second chances, only kill or be killed. Now it's up to this diverse and inexperienced squad to fight side by side, relying on each other to live through a reality where the only thing between them and death is a thin line.