Geeky university student Naofumi Iwatani goes from second-class citizen to second-class hero when he's summoned to the videogame-like kingdom of Melromarc. Known as the weakest of four heroes, the Shield Hero, he';s tasked with defending the world from calamity. But when Naofumi ends up betrayed and belittled from the start, will this hero-turned-cynic still be willing to fight?