In modern Japan, Atsume Yuma, a quintessential corporate drone, was once again working overtime alone at the company today.

Just then, Atsume found a mysterious contract on his desk. Seeing the oddly worded document, Atsume, thinking it was a colleague's prank, signed it.

Immediately after, a mysterious man appeared in the supposedly empty office and, in accordance with the contract's terms, assigned a beautiful girl as Atsume's attendant before sending him to his new workplace.

Thus, Atsume was transported to another world as a Dungeon Master.

However, even though the dungeon's location was supposed to be random, he was transferred to the capital of a major nation, a natural enemy of dungeons.

In this land, can Atsume create a dungeon?

For some reason, Atsume, who transformed his dungeon into a diner, continues to build his dungeon while popularizing Earth's cuisine.

This is the story of a certain Dungeon Master who eventually became known as the worst Demon Lord in history.

※Note: I haven't been able to reply to comments, but I read all of them! I sincerely apologize for my inability to reply!

On July 22, 2017, it reached #1 on the overall ranking! Thank you very much!

On July 27, 2017, it reached #1 on the weekly overall ranking! Thank you very much!

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