Naofumi Iwatani, an uncharismatic Otaku who spends his days in games and manga, suddenly finds himself summoned to a parallel universe! He discovers he is one of four heroes equipped with a legendary weapon and tasked with saving the world from the prophesied destruction. As the Shield Hero, the weakest hero, everything is not what it seems. Naofumi is soon alone, penniless, and betrayed. With no one to turn to, and nowhere to run, he only had his shield. Now, Naofumi must rise to become the legendary Shield Hero and save the world!