Manga like Minikui Orc no Gyakushuu: Doujin Eroge no Kichiku Koutaishi ni Tensei shita Moo no Junan

Rui, a mediocre college student, was shocked as he looked at his reflection in the mirror. The reason being that he had transformed into "Ludwig," the depraved crown prince of a grotesque, hardcore indie erotic game, whose appearance resembled a bloated orc, dedicated to subjecting the heroines to humiliation and training. While he instantly comprehended that he had been reincarnated into the world of an erotic game, unfortunately, this game only offered bad endings.

Above all, in his previous life, Rui was a socially awkward guy, with minimal opportunities to interact with girls, limited to receiving change at a convenience store. Trying to fulfill the game's scenario of humiliating and training the heroines was an impossible feat for him. The only salvation was his knowledge from thoroughly playing erotic games in his previous life and the fact that he had been transported five years before the main story began.

Rui... no, Ludwig made up his mind. He would do everything he could to slim down and present himself in a more favorable light to the heroines, in order to modestly survive and avoid triggering any destruction flags. However, Ludwig was unaware. Little did he know that by shattering these flags, he would end up significantly raising the heroines' favorability in a different way, leading him to encounter a future fraught with turmoil.

(Source: Novel Updates)