Krysta has been hunting vampires for 6 years with the healing assistance of her brother. She can see auras which give her an edge. (Of note- vampires are orange, Immortals a mix of purple and white, and Seth is bright white; David still has a hint of purple in his). Krysta and her brother are also "gifted ones" who can be successfully turned and made immortal.
Etienne comes across her while hunting and is intrigued. I enjoyed the interactions between all of the characters; it is clear each loves/respects each other. The story-line from previous books continues here- trying to find a way to stop/slow down the vampires madness and the mercenaries are back. I am intrigued by Zach and look forward to his story (which is next with Lisette's!)