Scotopia: First Dusk by Spencer Pizzani

In the shadows of Morton City, children are screened in secret for the gift driving a secret war. Selwyn has always embraced her elegant darkness, from her gothic style to an affinity for the sublime. When an impossible illness threatens her sanity, her attempts to uncover the truth will attract the attention of a dangerous organization wielding more than influence bought by corruption. Suddenly, everyone but her knows the rules of a deadly game where she has become the prize. To survive, she will have to learn the depths of her Scotopia, and learn why the darkness within her is more than just a calling.