The Unimplemented Last Bosses Became Allies.

Shutaro, the protagonist, was chosen for the free tier of the new VRMMO "Eternity." He obtained the "Dungeon Generation" skill through a random draw and immediately activated it. At the same time, due to the rampage of the mother AI, players were trapped inside the game, turning it into a death game where game death equals real-life death. Shutaro, who activated his skill at the start of the death game, found himself in a mysterious area called "Los Maola Castle." There, he encountered the Demon Lords who govern each of the six worlds. By a strange turn of events, Shutarō ended up subjugating them and now aims to escape from Eternity, which has become a death game.