The book Thrall the Daughters of Lilith by Jennifer Quintenz is an action packed book with romance, too. This book is about a girl named Braedyn who finds out she is half lilithu (a demon-usually a female that feeds off of men). She was raised by a guard (demon hunter) named Murphy who is known for being one of the best guards. The Guards knew they would eventually need a lilithu on their side, so that's where Braedyn comes in to play. Many of the other guards think she will follow her lilithu sisters and join their side, so many do not trust her or many would like to kill her.