Miyama-zero

In Japan, where dungeons are now part of the modern everyday life, Irikawa Haruo, who worked for a black company, purchases a house from a college junior for an unbelievably low price. However, a dungeon has appeared in the terrain of said house, and the law requires Haruo to manage it. Leaving behind his job at the black company, Haruo takes on an even harder job of dungeon management...!! https://www.ganganonline.com/title/2475