In the original fairytale, the difference between the sisters is number of eyes! Her three-eyed younger sister and one-eyed older sister treat the main girl badly because of she has two eyes "regular people." My original idea was for this story to abstract this into a world a million years from now where people evolved in tons of different ways, in a society which valued uniqueness and popularity above everything else. But a lot of the world history stuff didn't make it in, so it's good to know that it could still be more obvious! Thanks for your feedback!!!