This was very different from any YA novel I've read, and it was very clever in its subversion of the notion of "muses" and the nature of art. It is definitely on the slow side and has quite a bit of detail regarding art (which is very accurate and well-done, and I say this as someone who studied a lot of art history in college), so it's definitely not a novel for everyone. Julien is an interesting narrator, rather sensitive, and a bit unexpected. I actually liked that Paris is the setting, but since its Julien's every day life, it didn't function as a character in the story, as many YAs set in that city do. 
 Again, your results may vary, because this is a very unusual sort of book, but if you're looking for something a bit different, which art, mystery and magical realism, this one is a good pick. 
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 Paris! Art nerding! Feminist twist! 
 I'm guessing this will be a Sarah book, unless the tiny summary is wholly misleading.