You're being a SJW again. "Why do you complain about female knights in a story where magic and dragons exist?!!!". Just because one element is fantasy doesn't mean all plausibility is thrown out of the window. I LOVE serious, grounded stories that feature ONE fantastical element, hence why I keep watching isekai anime. It's why I love Death Note. It's why the origin stories of all the Marvel-movies are fun to watch where the hero awakens a fantastic ability and shows how that works in combination with the real world. So that's what I expected here. I didn't expect a more gore-y Boku no Hero Academia. That is my fault, admittedly.
When I started watching this episode 1, I just kept thinking "why isn't he going to the police?", "why isn't he going to the government to be put in an institution for orphans?" and "why does he not run away? Yakuza won't be able to find some random kid". The anime didn't take the time to introduce us to its world properly and while that might still happen in the future, it's not a narrative structure I like.