MTL - The Corpse Ruler Confuses the World, All Seven Husbands Are Devils - Chapter 22 Come on!

Our straight (?) bottom woke up ten years into the future and found himself on the bed of his childhood friend… At the start, the bottom was shocked to his very bones, but he soon quickly accepted this premise and found the whole situation to be rather amusing. Precisely then, the bottom once again went back to his timeline — back to when he and the top were just platonic childhood friends.

Landmines include but are not limited to: Sweet & naive bottom, a president story, logic is dead, slow-progressing romance, the protagonist’s name has too many character strokes, the names are hard to pronounce, too many gay characters…

- Description from novelupdates

The dark underground dungeon was filled with countless ancient relics and treasures. Eerie, deformed, cursed objects... The abyss, catacombs, Ancient Gods, mythical races... Mechanics, cursed seal implants, and the gargantuan black towers... A peculiar mix of Alchemy, a drop of steampunk, two spoons of supernatural mystery, blending into a vibrant and colorful fantasy world. I am a puppeteer Alchemist. All that my eyes behold, becomes my puppet. Alone, I am an army!

The leader of the thousand demons, the Demon God Chun YeoWoon. Due to an unfortunate accident, he had been sent to the distant future.