The opera-novel's first-person retrospective narrator is smart and clever , but the novel itself casts him into doubt: he is a self-acknowledged unreliable narrator, and perhaps even a narrator suffering weird delusions and a memory disorder. The book starts (several times, in fact) with a usual setup, a comfortable framing of the story to follow, and then gradually --- through judicious and entertaining use of stage directions and references to different leitmotifs, staging, costumes, and orchestration cues --- the story becomes more and more sinister, as well as deranged and unbelievable and nonsensical. The narrator tries to describe things he witnessed, except he can't quite describe exactly what he witnessed, so he ends up describing everything in hedged and allusive terms. This manages to be oblique about plot details while being explicit about sexual details, which is weird but not so gross and repellent that it would stop me from reading more, to see what happens. (I believe the usual mode is to now compliment the author: that was masterfully done, to describe so much while leaving everything utterly uncertain!)
The conclusion, of course, is as in every opera: a dramatic death scene.
But the story, and its light fourth-wall-breaking, does not end there. Even as the death scene denouement trickles to a feeble closure, the narrator refers to how incomplete the tale feels and how much of the novel is still in your right hand! This obviously is only true for physical copies of the book, but as luck would have it, I was reading a physical copy, so this trick landed and seemed cool and witty. Then the remainder of the book was even more disjointed and off-the-rails, with the added twist that maybe every 2 or 3 pages, Handler masterfully convinced me that either (1) it was all real, and this was a sort of fantasy-nightmare world, or (2) the narrator was having a mental breakdown, which we were seeing from the inside. The first such switch is neat. The switch back requires overcoming some reasonable skepticism. The next switch, and the next, and the next? I don't know. I oscillated between believing the book literally and disbelieving every single event, and that is a precarious balance to strike, and an astounding effect to sustain for so long.
In conclusion, I liked it, even though the subject matter was squicky.
This post's theme word is sercroupierize, "to have sex with several people in succession." (Not in many online dictionaries, apparently.) The book's sercrouiperizing narrator was very off-putting, but somehow always turned-on.
 Many iconic children's movies start with the double murder of the protagonist's parents, so... I'm just saying, any cognitive dissonance you may have with my downplaying of murder as on par with sarcasm, and completely suitable for children --- take it up with the culture-makers. I'm just an observer.
 The sex scenes may be breathless, but they are also not terribly erotic. They're just kind of... the shotgun approach to horniness, where everything gets utterly slimy and the characters have to take breaks every few hours for coitus, for no apparent reason.
 Well, he's either "smart and clever" or "incompetent, idiotic, and deranged". It's hard to tell. You'll see.