A "speedrunner" decides, oh yes let's make the game take essentially 100 times longer on his first run and gets forcibly reincarnated.... the world only sees him as an error, people consider him with no talent, and this is a complete wash of a book. Sorry but too many inconsistencies make this an annoying thing to read, if you get past that, it may be interesting, but the protag ain't a speedrunner, he's just a plain masochist
PS I actually got confused if the mc had breasts or not in the first chapter before he was reincarnated, I don't know why, but I did