D Genesis: Dungeon ga Dekite 3-nen  

D-Genesis: Three Years after the Dungeons Appeared, Dジェネシス ダンジョンが出来て3年, D Genesis: 3 Years after Dungeon Appeared

Three years ago, a dungeon appeared on Earth after an experiment in Area 51 went wrong. Now people explore these monster-filled labyrinths for wealth, power, and magic. Keigo Yoshimura is an office worker who dreams of quitting his job to live the easy life. During a business call, he discovers the birth of a new dungeon and gains a magical skill that turns subterranean exploration into an RPG. As the world's top explorer, Keigo earns money with help from Azusa Miyoshi, his mathematically gifted colleague and business partner in dungeon diving. However, he faces scrutiny from military, government agencies, and even more sinister forces, making it difficult for him to achieve his dream of living an easy life.

D Genesis: Dungeon ga Dekite 3-nen began as a web novel on Shousetsuka ni Narou on June 1, 2019. The first official volume was published on February 5, 2020 by Kadokawa.The series has been published digitally in English as D-Genesis: Three Years after the Dungeons Appeared by J-Novel Club since July 7, 2022.