Luna is about Reagan's brother Liam. Liam doesn't like who he is, he wants to be something different, something he is inside. He wants to be Luna. Reagan is used to keeping her secret, but now Luna wants to come out in public. Things begin to unravel, and Reagan doesn't know what to do.
I really enjoyed this book. I thought it was a really good angle to not just write it in the perspective of a sibling, but of the sister. It then shows how Liam was jealous of his sister all through the years. It was well written, I liked both Liam and Reagan, and the family dynamics were intriguing and showed all the gender stereotypes. It also had a fantastic ending.