I'm a librarian who loves anime, manga, and reading a wide variety of genres.
After one last big push, I finally managed to finish this.
Unfortunately, it kind of sucked. Not only was it massively boring, I managed to figure out who was most likely the murderer well before the ending. Not because I'd actually figured out how the murders had been committed, but because there was one glaringly obvious motive. I figured that maybe it was a red herring, but nope. And the moai puzzle itself required enormous leaps of logic.