Manga 165028 I Killed An Academy Player

This power fantasy Manhwa features someone who reincarnated into his video game as a side character and has to become the main character to finish the storyline, specifically changing the storyline to have a better ending than any of the routes originally in the game. The game is a dating sim RPG but this manhwa doesn't actually lean too hard into the RPG elements unlike most stories in this genre because the main character is only meant to be a side character without full access to the main character UI. This story features a slight romance element but it's all one-sided as in typical anime ... fashion, the main character has other things on their mind but they do bring it up occasionally.

Despite the dating sim aspect of the game, there's not much to do with it and the story is mainly about how the MC uses his knowledge of the game change the storyline (and deal with the unexpected outcomes of those changes) so the characters don't really feel like fleshed out characters, just tools for the MC to develop and use. There's a lot of weird socks and bare feet in this manhwa, so I'm pretty sure either the artist or author has a foot fetish.

The MC is pretty obviously portrayed like a good person with a bit of a scumbag, and I think the author does a good job of conveying the feeling of being a gamer trying to 100% complete the game with the best ending into the main character's personality. It's not the most well developed story or cast, but it's very entertaining to read.