Due to certain circumstances, ordinary high school student Misumi Makoto is summoned to another world to become a Hero... at least, he was supposed to be one. However, despised by the Goddess for a ridiculous reason, Makoto is banished to the barren Wasteland. At his wit's end, Makoto wanders the wasteland, where he begins to make friends with Highland orc girl Emma. However, when Makoto learns that she's going to be sacrificed to the greater dragon Shen...

Makoto forms a favorable contract with greater dragon Shin. Shin takes him to her demiplane, another world that exists within her mist. Blessed with fertile lands and hidden from the Goddess, Makoto develops the demiplane along with the Highland orcs who have settled there. Meanwhile, outside the demiplane, the Black Spider of Disaster driven to madness by her eternal hunger closes in on the demiplane.

Makoto is entered into a contract with the Black Spider of Disaster while he's unconscious. Despite his confusion, he gives names to Shin and the Black Spider of Disaster. Meanwhile, various demihumans including the elder dwarves begin settling in the demiplane. Surrounded by demihumans, Makoto begins to miss humans and heads to a human town. However, he finds armed humans waiting for him! Why would they do this?!

In the human town of Zetsuya, Makoto and company meet a girl named Rinon who is searching for her missing sister. That night, they're attacked at the inn. They learn Rinon's sister Toa is being held captive because of her debt. As Makoto nearly loses his cool for certain reasons, Tomoe and Mio go to rescue Toa instead. However, a single man stands in their way.

Makoto leaves behind the destroyed town of Zetsuya and travels towards a new town with Toa, Rinon, and other adventurers. While defeating many monsters on the road, the group safely arrives in Tsige. Sorry to see Toa and her party go, Makoto suggests they throw one last party. During the party, Makoto hears an unsettling rumor about the Rembrandt Trading Company, the client of his first job...

Makoto's party accepts the Rembrandt Trading Company job. They've already acquired the necessary materials, and their first job as adventurers seems to be going well... But trading company owner Patrick Rembrandt distrusts Makoto, as he lacks any kind of adventuring record. Furthermore, Makoto seeks to join the merchants' guild, where two tests await him.