The World After the Bad Ending - Chapter 106

In this school fantasy story set in the distant future, creatures contaminated by pollution have overtaken the land, forcing humanity to live in isolated mobile cities called Regios. One such city named Zuellni is a self-contained school in which freshman Layfon Alseif has just enrolled. Layfon reluctantly joins the 17th Military Arts Platoon led by the third-year student Nina Antalk and embarks on a series of adventures.

Follow Chen Ming as he accepts disciples, establishes a sect, and fights his way in a world that deems him a cannon fodder.
He goes against any common sense using his wits and novel knowhow to finish missions and arm himself against his cruel fate.

- Description from Novelupdates

Office worker Leon is reincarnated into a particularly punishing dating sim video game, where women reign supreme and only beautiful men have a seat at the table. But Leon has a secret weapon: he remembers everything from his past life, which includes a complete playthrough of the very game in which he is now trapped. Watch Leon spark a revolution to change this new world in order to fulfill his ultimate desire…of living a quiet, easy life in the countryside!