Loved the concept and the exploration of Evelyn and Martine's characters. Unfortunately I'm one of those people who does just need SOME world-building, or at least a reason we're not given any world-building (e.g., Wilder Girls, where we read entirely from the perspective of the girls on the island and they have no way of knowing what's happening in the wider world). 

I just have so many questions! How did this world get from our current ethical rejection of cloning of humans to apparent widespread acceptance of fully sentient human clones treated as disposable? Why was infertility integral to the ethical acceptance of the clones but their own sentience irrelevant? How did Evelyn keep her gruesome methods secret from the people presumably purchasing clones? If even a small number of these clones are in the world and any of them are in any way as obviously sentient as Martine, surely people other than Nathan are getting attached to them and considering them people? I guess to me the humanity (or not) of clones is by far the most interesting part of the premise, but it's far from the main concern of the narrative, which left me wanting a very different story to the one we got.