Legacy (The Descendant Series Book 3). DESCENDANT, #3

After the chaos of Mexico, Abby and Kye have lost everything but each other. They're on the run with no purpose, no allies, and very little money. To make things worse, Abby's wound from the Arawn Dagger is draining her power, leaving her unable to access her Light, or her Healing ability. While the hunt for her long-lost father takes them back through Abby's childhood homes, they're forced to question everything they've been taught and everyone they've ever trusted-including each other.
After a desperate attempt to Heal Abby's wound goes horribly awry, and with the demons they thought they'd lost hot on their heels, the star-crossed couple is forced to face some painful realities that will change life for everyone they know. When Abby's best friend is kidnapped by demons, Abby and Kye abandon their search and launch a rescue attempt that morphs into a battle, the outcome of which will determine if Abby and her friends have what it takes to rid the world of demons, or if the royal bloodline and the Gifted generation will be obliterated once and for all.