I know that isekai is sort of an entire genre's worth of self-insert-fic. I am largely at peace with that!
Even then... I was already cringing really hard ten pages in. This is embarrassing to watch. If it were just a eight-year-old's concept of what being clever is like mixed with an overblown sense of self-importance, I could say it's cute or something and stomach it, but it's trying pathetically hard to be edgy, too. I just can't.
Honestly, parody-depictions of chuunibyou fantasies are frequently more compelling and less cringeworthy than this. XD
Disclaimer: I only made it through the first chapter. It's possible it gets better. I mean, that is a thing that happens sometimes. Right? Yet, somehow I find myself saying with absolute confidence, that that's not what's going to happen here. This is one of those things where you just know that you've only yet seen the tippy-tip of the dumpster fire; where beneath the surface an entire landfill's worth of garbage lies smouldering.