I still don't rate it because I'm really confused. First, because it really seems like this is the very last book of the series! There are not any new books announced. And honestly, currently I prefer Thunder Girls. I can't help it, but GG has never seemed so weak as now.
Now the three Fates are girl goddesses. They are representing totality of fate, which is expressed with their racial diversity (although not so in the book). The cover is not like the Fates in the book.
By the way, Clotho is the blue one of the triplet. The cat is also in the book and so is the spider....it's Arachne! (Do you remember her from Athena the Wise? Wow, let's see, whether our snarky spider gets a happy end!). Spiders are the perfect match for the spinning and knitting Fates!
The basic idea is interesting because mortals complain about their fates and are angry of the particular three goddesses. Clotho wants to change that!
There are interesting mythological attempts, but I'm not 100% persuaded. First, there's the famous Underworld sinner Tantalus introduced in GG world.
Then, we have Atalanta (from Medea the enchantress), but there is no recall of her part in Aphrodite the Beauty. It's a bit confusing, when later books have earlier mythological events.
Last but not least, there is the serpent from Medea the Enchantress. There's a very interesting attempt, but the problem is solved too early. I'm not really satisfied with Clotho's strategy, although I like the idea behind it.
(Spoiler:
Please give the serpent a real friend or another job, like protecting the golden apples of the Hesperides!)