The Sister complicated? It's like a small town. You have to live there a while before you get to know what's going on, but once you connect, there are several levels. Mainstream and underground. 
It's like getting introduced to a bunch of people at a party. At first, you struggle with their names. After a while, it's like you've known them forever. The Sister is like that, once you get through the introductory scenes. I always felt if the reader was able reach that position, the story would get better and better.