You Want Me to Leave the Army? I'll Rise Against the Tide in 1937!

He has enlisted four times and been sent packing four times. Everyone in the district knows that Base 042 has a madman named Lin Yuan who just won’t leave. To get rid of him, the company commander takes heart pills, the demobilization office lady tears her hair out, and even the stunning female commander pulls her sidearm. “Get out now, or I’ll shoot you!” Lin Yuan glances at the System countdown and pushes open the barracks door behind him. “Don’t shoot! I’m turning it in!” The doors swing open, and on the other side lies a parallel world under invasion by foreign enemies, its land shattered and its people suffering! He looks at his compatriots across the way, struggling to hold the line with outdated muskets, then at Lin Yuan’s roguish grin. The gun slips from her hand. The entire military district is left stunned and shaken to the core! That very night, the High Command issues a direct order: “Seal off the base! Move in! Get the heavy combined-arms brigade through that door!” Facing bandits from another world with woefully outdated equipment, Lin Yuan lights a cigarette as he strides in his exoskeleton armor. “I hear you’ve got numbers on your side? Too bad. Everyone on our side suffers from a fear of not having enough firepower!”