After a freak lightning accident zaps him dead, 15-year-old Mochizuki Touya wakes up to find himself face-to-face with God. “I am afraid to say that I have made a bit of a blunder...” laments the old coot. But all is not lost! God says he can reincarnate Touya into a world of fantasy, and as a bonus, he gets to bring his smartphone along with him! So begins Touya's adventure in a new, anachronistic pseudo-medieval world. Friends! Laughs! Tears! Inexplicable Deus ex Machina!

A certain college girl who's loved books ever since she was a little girl dies in an accident and is reborn in another world she knows nothing about. She is now Myne, the sickly five-year-old daughter of a poor soldier. To make things worse, the world she's been reborn in has a very low literacy rate and books mostly don't exist. She'd have to pay an enormous amount of money to buy one.

Juliette Contzen is a lazy, good-for-nothing princess. Overshadowed by her siblings, she's left with little to do but nap, read, and occasionally cut the falling raindrops with her sword. Spotted one day by an astonished adventurer, he insists on grading Juliette's swordsmanship, then promptly has a mental breakdown at the result. Soon after, Juliette is given the news that her kingdom is on the brink of bankruptcy. At the threat of being married off, the lazy princess vows to do whatever it takes to maintain her current lifestyle.

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

Naofumi Iwatani continues his adventure in this second volume. But his task is not yet complete and obstacles mount as the increasingly ominous waves of destruction approach. He finds a new friend and new powerful abilities that may prove to be too dangerous for the companionship. Will Naofumi live up to his role as the Shield Hero and save the world from its prophesized destruction? Or will his dark side consume him?