Betrayed by her ungrateful Fox-shifter fiancé, Sienna finally snaps and cuts him loose. But her life takes a dangerous turn when she finds a wounded, SSS-rank Naga hiding in her car. As he enters his "Heat Phase," the icy predator turns into a feverish lover who refuses to let her go. From a lab fugitive to a devoted protector, Caspian will show her that while a fox can lie, a serpent loves for eternity.