After dying a laughable and pathetic death on his way back from buying a game, high school student and recluse Kazuma Satou finds himself sitting before a beautiful but obnoxious goddess named Aqua. She provides the NEET with two options: continue on to heaven or reincarnate in every gamer's dream—a real fantasy world! Choosing to start a new life, Kazuma is quickly tasked with defeating a Demon King who is terrorizing villages. But before he goes, he can choose one item of any kind to aid him in his quest, and the future hero selects Aqua. But Kazuma has made a grave mistake—Aqua is completely useless! Unfortunately, their troubles don't end here; it turns out that living in such a world is far different from how it plays out in a game. Instead of going on a thrilling adventure, the duo must first work to pay for their living expenses. Indeed, their misfortunes have only just begun!

The story continues to follow Kazuma and the rest of his party through countless more adventures as they struggle to earn money and have to deal with one another's problematic personalities. However, things rarely go as planned, and they are often sidetracked by their own idiotic tendencies.

Kazuma Satou, former NEET and current reincarnated adventurer, finally returns home after the incident at the Crimson Demon village. Following their recent exploits, the party is one step closer to vanquishing the Demon King and his armies—a terrifying task that Kazuma is eager to ignore for as long as possible. Things, however, are not going as smoothly as the group would like; they are constantly racking up debt, getting sidetracked during missions, and falling into traps due to their recklessness and eccentricities. As the party struggles with their perennial issues, they receive an invitation from a princess interested in hearing tales of the group's "heroic" deeds. Darkness' pleas to refuse the invitation only fire the others up to accept it, marking the start of yet another uncanny adventure with unforeseen consequences.