Rise of the Winged Assassin - Dodie Huber

Born into a winged warrior race, Lorelei knows how to wield a sword. Now that she is seventeen, her swordsmanship is tested, and when she passes, she's removed from her family for further training to prepare for war. But deep underneath the surface, she faces a greater threat, more formidable than their enemy, the Toraveru. Exposure to battle has awakened a deep-seated psychological disease that will prey upon her emotions, challenge her loyalties, twist her morals, and breed an unquenchable thirst for violence. The elders call it the Renai, and they believe there's only one cure for the infected: death by execution.

As she struggles to fight against the disease, Lorelei's strength and resolve begin to wane, but she finds hope when she's sought out by Airik, a dangerously infected, exiled mercenary who tells her the urges she's struggling to restrain can be forged into powerful abilities that have been suppressed by centuries of executions. Shaken by the truth, Lorelei begins to question what she's been told about the disease, about the cure, and about the motivations of her honor-bound race. In order to survive, she must place her life and trust in the hands of dangerous allies and learn to wield the power of the Renai before it's too late.