Guardian Seductress by Gracie C. McKeever

Genre: Urban Fantasy/ Shapeshifter/ Interracial [contains graphic sexual content and adult language] When the mysterious Genesis shows up at Alex Ryan's condo claiming to have known Alex's mother, warning that his father's death was no accident, and that Glenn Ryan wasn't the target, Alex thinks the woman is stark raving mad. Once Genesis explains that she is not human, and has been watching Alex since he was born, he is certain of it. Genesis is Inanna, an ancient race of people who subsist on the energy they regularly siphon from humans through sexual intercourse. But one of their own broke the sacred covenant twenty-eight years ago when she gave birth to the cambion, Alex Ryan. Now, time is running out. A power struggle is afoot in Emsharra, and a major shift is about to occur. The insurgent doesn't want any loose ends threatening her rise to power–mainly the only other blood kin of the current Quna: Alex Ryan and his treasonous guardian, Genesis. Tropes: Warrior Woman, Female Protector