Remember in chapter 1 or 2 when there was an overarching plot seemingly being setup about maybe the game world being real, the MC's mom being a vampire irl, and maybe this actually being her real body or something? And her parents made the game for her? Idk. Something along those lines. Anyway...
Author. You've already committed to writing erotica. There's already insertion. There are other peers in your genre that show full sex scenes. Savage hero, isekai meikyuu de harem o, reincarnated carrier. We're not here for blueball gags. Get with the program or gtfo.
Grown man acting like a teenaged girl. Would've rather it just been a teenaged girl character, but since the story invoked gender bender, I'd at least expect some mismatching in expected behavior. If you removed chapter 1, the rest of the story would flow just as it does. But now there's a...
I think I hate the princess more than the MC. She's the cause of all MC's major problems and she accomplishes nothing by herself. Name me one time in this entire story that the princess wants something done and she doesn't immediately volunteer MC to do it for her. She wants to become queen, but...
Author sans, author sans! You can create interesting stories with conflict without everything having to be forced and without having to write characters that have less brain activity than 5 year olds, author sans!