First, I loved the world building in The Belles! It was pretty unique with a blend of magic, mythology, and science. I found the descriptions of arcana magic and court politics for the most part entertaing. However, right around the 40% mark, I was getting a little bored of all the fashion and beauty makeover descriptions. The big conflict and antagonist wasn't really introduced until 60% which after 8 hours of beauty treatments, I was a little bit over it. Granted, I generally like pretty fast paced novels, but had I not listened to the audiobook (as opposed to reading it), I don't know that I would have finished it.
Second, I pretty much liked the characters which is a must for me to enjoy any story. Camellia is ambitious and smart but a naive about people and court life in general. She has a pretty good cast of supporting friends and her two love interests are ones you're rooting for even if it's not super developed. The villain is really devious and you can't help but despise her, though I wish Clayton would have introduced her sooner to move the plot along faster. The big mystery wasn't that big of a mystery and all the action happens in the lady 100 pages which drives me crazy about YA books!
There are some great points about beauty and privilege and societal expectations that would make a great book discussion. Overall, decently entertaining with good characters. I world be interested in reading the next one- especially since it's 100 pages shorter.