So who is Zee? I think she's an interesting idea.
What happens if you take a person and set out to remove them from the labels that we often use to define humanity? First of all, this girl has been genetically altered - not in a fixed way, either. She doesn't bear the constraints of normal people - the need for a particular mix of chemicals in the atmosphere or in food...
Then, she's been removed from a human social context - raised among living beings who don't even see the world in the same colours that Zee does. She inherits a range of unconventional attitudes.
And lastly, the idea that a human is a body that houses a single consciousness - we're taking that and altering that, too. Zee is now a house for two distinct identities, one very peculiar one. And yet what's left is still, I think, very relatable and very human.
There again I could have it all back to front. Perhaps the human experience is all about the things that distort our identities... :)