To Believe Duology.

With darkness threatening to take over, Lili is on the treacherous path to becoming the next bloodthirsty ruler of Neverland. The struggle to resist her dark side becomes more difficult when her twin sister, Lia, arrives and is accepted instantly. In order to better her chances of saving Pan, Lili works to learn more about her adversary and the world she has come to know.

The war with the dark side becomes more personal for Lia when her twin sister becomes Pan’s new queen, just as evil if not more cruel. A harsh winter is taking its toll, changing Neverland; and Lia is the only one with the power to return the island to its natural state—if she can steal enough magic from Pan that is. If she can fight the urge to give up and let Neverland swallow her whole, she can take down Pan and Lili for good.

To Believe in Peter Pan (Book #1)
To Believe in the Demon King (Book#2)