Possessed (Hades Castle Trilogy)

I'm struggling with my evil side—the demon known as Lilith—and only Samael can help me. Unfortunately, he thinks we're dangerous for each other—just because we murdered each other in past lives. And even worse, he believes he has to marry a mortal to keep me safe. A genuinely terrible mortal woman, I might add. But with the Free Men growing in power, we must join forces to stop their evil army. As we journey through Albia searching for them, we are drawn even closer together, bound by desire and our twisted love. As far as I can tell, one of two things will happen: either we will overcome our past, and defeat the Free Men together. Or our dark history will have us turning into monsters and tearing each other to pieces. I'm hoping for the first one.