This anime was pretty good, the animation was just " okay ", they didn't do so much rush and the ost was pretty good. but yeah there a big problem, in the last arc they changed everything, rushed everything, they killed the best arc of the manga, they killed the characters itself with a bad story who didn't even exist in the manga, and they can't do anything about this, they destroyed the anime with this. I don't understand why, it was good but they decided to destroy the good work of 16 episodes with the last arc, sadly like a bunch of isekai, this one didn't got a good adaptation.
Read the manga.