18+ Gedou Tenisha no Harem Dungeon Seisakuki

While all of his classmate were transported to another world as heroes, for some reason he was left out as the dungeon master... and he, Satoshi Shinta, became the world's enemy. As the enemy of humankind, in order to survive and live a pleasant life in another world, he had a big choice to make... Through devilish methods, make his enemies fall, and strengthen his dungeon!! To violate his enemies or kill them, the curtain raises on (male) Satoshi Shinta's devilish dungeon management!!

(Source: Takeshobo, translated)