The Protector's Heart by Bryony Kildare
When Brietta Larch, a half-blooded Fae apprenticed to the Druidic Circle of Chicago, begins to receive menacing text messages that seem to be from a vampire, she immediately knows the danger is real. Yet no one around her seems to take them seriously - not her mother, not her best friend, not even the peacekeepers an increasingly frightened Brietta reaches out to for protection. But when the vampire attacks her in the middle of the marketplace, one person reacts: Alejandro Halcon, a peacekeeper who has trained himself to see past even the most powerful illusions.
Yet even under Alejandro's protection, Brietta's life begins to fall apart as her stalker manages to get her dismissed from her apprenticeship. To escape the reach of the enemy's spells, the two half-blooded Fae must retreat to the Old World, the lands of Faerie separated from the human world centuries before. There they must discover the key to the vampire's illusions, even as they try to navigate the difficulties of the new love that has blossomed between them. Brietta, independent and strong-willed, has never before even considered submitting to a mate. Yet as she comes to rely on Alejandro's strong and tender discipline, she realizes that she has been denying a part of herself all her life. When Alejandro leaves her in the Old World to be trained by the beautiful Fae healer Leithril, Brietta is determined to learn submission and become worthy to be claimed as his mate. But as weeks pass and Alejandro does not return, she begins to fear the worst. Brietta must find the strength to save her beloved...or face the loss of all their newfound hopes and dreams.
This is a standalone novel and does not need to be read in order as part of the series.