敏腕コンサルタント・江副和彦の自宅の庭に謎の地下空間が出現。興味本位で踏み入ると謎の美女・朱音が現れ、今後世界中に現れる666のダンジョンを10年以内に攻略できなければ、“魔物大氾濫”により人類は滅びると告げられる。江副は滅亡を防ぐため『株式会社ダンジョン・バスターズ』を起ち上げ、仲間とともにダンジョン攻略へ挑むが――!?
Clear all the dungeons! There are 666 of them and 10 years to do it. If not, the only thing that awaits…is total annihilation. Ezoe Kazuhiko suddenly finds a mysterious underground space in his yard. When he steps into what turns out to be the very first dungeon in this world, he ends up activating the Dungeon System and learns from the mysterious beauty who appears to him, Akane, that the world is doomed to destruction if the 666 total dungeons that will be appearing in this world are not all cleared within 10 years. As countries begin taking measures in response to the dungeons appearing all over the world, Ezoe seeks out companions together with whom he establishes Dungeon Busters Inc., a company dedicated to clearing all the dungeons in the world! The curtains rise on this dungeon-delving epic with overwhelming realism!
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