Glows by C.K.Madden

When Skyla, a Light Glow on Earth to help Normals (humans) stay clear of darkness, meets Julien, a fellow Glow, her world is turned upside down. The two discover that things are not always as they seem. Set in a world that is ripe for intrigue, betrayal, and undercover agents, Skyla and Julien must decide whether they can work together to save mankind even if it means losing everything, including their own lives.