The ultra-practical third-year in junior high, Yusuke Yotsuya, is still stuck in this alternate universe where his next quest is to "transport cargo." While on the journey, he and his party rescue a platoon of soldiers being attacked by monsters who join them on their way. However, the soldiers, who hail from a military power, had actually been on their own journey to publicly execute supposed heretics in their custody―including a child! As if this political dissent and religious conflict weren't enough to contend with, Yotsuya and the gang then find themselves trapped in the dungeon of an ancient cavern. Yotsuya's a far cry from the "ideal hero" in this world, so what secret plan will he concoct to get them out!?