I suppose the protagonist is Desiree, but it's hard to tell with the way the story is written. Some of her positive traits are that she is incredibly smart (she reads books by people like Stephen Hawking), and she is an april witch. Her obvious negative trait is that she is so crippled she can't move or talk. She is also a very jealous person, especially towards her "sisters", but this is pretty understandable. These traits are pretty much the entire reason for the plot. If she didn't have them, there really wouldn't be a story.