Avalon of Disaster

A brief description of the manga Avalon of Disaster:

I”, a company employee who used to be a serious gamer, was transferred to the VRMMO “Dunex” world where I played it to the bone… but to my surprise, I turned out to be a fat, hated villain of the explorer school!
I’m seriously starting at the bottom of the class, with the lowest physical ability, and even losing to the slimes in the dungeon!　And in the future according to the scenario, you don’t end up with your beautiful childhood sweetheart, and you end up being expelled from the school!
In order to avoid the worst possible outcome, the goal is to lose weight and level up as fast as possible!　Using his knowledge of the game, he will also obtain a harem and the position of a shadowy hero!
With a cool-headed ambition to find the fastest and most optimal solution, I began to conquer this “world too bad to be true, like a shitty game”. ……?