After a traffic accident, Kazuma Sato’s disappointingly brief life was supposed to be over, but he wakes up to see a beautiful girl before him. She claims to be a goddess, Aqua, and asks if he would like to go to another world and bring only one thing with him. Kazuma decides to bring the goddess herself, and they are transported to a fantasy world filled with adventure, ruled by a demon king. Now Kazuma only wants to live in peace, but Aqua wants to solve many of this world’s problems, and the demon king will only turn a blind eye for so long…
Darkness, Aqua, and Megumin are back to continue their quest against the Devil King. Kazuma is back too, but the only adventures he has waiting for him exist within the criminal justice system.
Kazuma and Aqua meet Yunyun, a Crimson Demon girl who claims to be Megumin's rival. The feuding magic users then square off in a competition that could have ruinous repercussions for both of them.
A new discovery in a previously mapped out dungeon might be the first step toward Kazuma repaying his massive debt. Unfortunately for him, Aqua is determined to help.
Darkness is back, but not to stay, if Kazuma and her father have anything to say about it.
With debt looming over her, Aqua convinces Kazuma to accept a high difficulty quest to purify a lake, which doesn't require killing any monsters.
Dullahan, a top leader in the Devil King's army, yet again appears at the city in a frenzied rage.
"I want money." After paying back the debt Aqua has racked up, Kazuma and Aqua's monetary situation grows even more dire. The party accepts a quest to kill helpless Snow Sprites and heads for the snowy mountains in order to escape from the stables during this winter so cold it freezes Kazuma's eyelashes solid.
Kazuma and Aqua can't properly accept rewards from quests due to their mediocre party lineup, and are so destitute that even keeping wood on the fire is difficult. Kazuma comes up with a plan and visits a magical accessories shop run by a woman called Wiz.
The party makes their way to Arcanretia, a city known for it's recuperative hot springs! But what they don't know about the city might spell doom for their vacation.
The rampaging ancient weapon: the mobile fortress, Destroyer, is headed straight for Kazuma and party's city!