I do agree that it's basically a very, very confused crime novel that doesn't know what it wants to be, though. I think it goes for a different take and if I'm being honest I prefer it over the book, though I'm sure a lot of people would disagree with me there. This is probably a result of the musical, although I don't personally think the musical is as apologetic for the character's actions or romanticises him as much to the extent that a lot of people say it does (just because a character is initially charismatic doesn't meant they are presented as a viable romantic option for the whole thing, people!). At this point I've seen people conflate this with the book character and you get people talking about this sad innocent bean/sexy bad boy version of the book character which is absolutely not in line with his characterisation at all (and some people go through a further development after a while for the book version and think he's cool and/or attractive for being insane and creepy) which is disconcerting to say the least. There's definitely a huge cultural expectation around the character now for him to be romantic or at least a sad innocent bean, probably due to the number of relatively more sympathetic adaptations (there probably were still horror enthusiasts who still viewed the character as a tragic grotesque or something but the general perception still changed).

I had a lot of random knowledge about the book before I read it in full since I was looking at stuff related to the musical and I'd expected a lot of the things that people were taken aback by. I still mostly found him to be a bit of a blank slate/author insert, but at least he was much more sensible. The Persian is fine but it's mostly because he has more interesting scenes talking with Erik, as he has to narrate for the bits where Christine and Raoul aren't there. Like she says some good things but then doesn't follow through with her actions, especially near the end? She doesn't really progress as a character and in the end her story is pretty much shunted to the side. I was actually really surprised by this when reading the book and I hadn't expected her to be. Yeah, but I've seen loads of people say that they love Book Christine, often accompanied with lengthy explanations, and that she doesn't become passive in the second half, and I cannot for the life of me understand that at all.

Phantom of the opera book explained