Man, another great question! And the answer is pretty simple: every character should have their own complex inner world. No paper cut-outs.

For example, her first love, Jorr, seems like the perfect man at first (read: a paper cut-out). But later, he does seemingly cruel things. He acts based on his own internal struggles--struggles which Raena knows little about. As she learns more about him, so too does the reader. This builds mystery and depth and curiosity about other characters--to make them not 100% open-book.