Dungeon of Oblivion

Hisou Katagi is a massive turboweeb. A true one, one of *those*. You know? The kind that facepalms my jokes on the hentai cringe games, defends absolute degeneracy like its his god-given duty, etc? The kind that thinks Shinji Ikari is a role model? Yeah, that kind. Even the other weebs bully him. He's too far gone. Thing is? Hisou is a massive lolicon, too. One day, after finishing his newest RPGMaker "ntr bait" woman humiliation game, he decided it was a good idea to actually fuck his own little sister in order to try and make her addict to his dick. Just like in his games. Reality and fiction are kinda blurred when weebs are gone this far, yo. However? Miraculously just before he carries out his plan, Hisou is actually struck by a truck! What a coincidence! Or is it?
Turns out God exists and she's actually a Goddess. Hisou's perverse energy and thirst was too strong for this world, so the Goddess intervened just in time. She sent Hisou over to the Soul Codex, the place where souls are born and return to be purified for reincarnation. In Hisou's case, however, she's giving him a trial. The Soul Codex created a massive dungeon seeded from Hisou's deepest perversions. And what's more? The Soul Codex has the ability to completely change him, body and mind. Will Hisou be able to safely navigate the dungeon of his oblivion or will he succumb to his own perversions and become a mindless subhuman cumrag just like those he enjoys making in his games? The karmic retribution has begun!