This is book number 1 in the Kingdom of Xia series.
"After discovering she's a serpent demon, Skybright struggles to navigate friendship, love, and her own darkly shifting identity. A richly imagined world and an unforgettable heroine make this a story that fantasy fans won't want to miss."— Meghan
Inspired by the rich history of Chinese mythology, this sweeping fantasy is set in the ancient Kingdom of Xia and tells the coming of age story of Skybright, a young girl who worries about her growing otherness. As she turns 16, Skybright notices troubling changes. By day, she is a companion and handmaid to the youngest daughter of a very wealthy family. But nighttime brings with it a darkness that not even daybreak can quell. When her plight can no longer be denied, Skybright learns that despite a dark destiny, she must struggle to retain her sense of self--even as she falls in love for the first time.