Wicked Dreams by K.G. Reuss

Being the Devil’s most trusted guard, Donovan Weaver had two tasks: 1) Guard Olivia, future Queen of the Underworld, and 2) Never touch her.
He failed on both accounts.

Donovan: I fell in love with the right girl at the wrong time. After the Devil found out what I’d done, he cursed me to a life of being an incubus and stealing women’s souls through their dreams. He knew touching another woman would be torture for me and was kind enough to bestow the curse of it for eternity.
But then, I see her in a dream. The woman I lost all those centuries ago when the Devil cast her out. She doesn’t know who I am, but that won’t stop me.
I want my girl back and will stop at nothing to get her. Even if it means killing her.

Olivia: Life has never been easy for me. Constantly bullied by my peers and labeled an outcast, my dreams are my only escape. They’re the place he is. Donovan, the beautiful man who comes to me in my sleep. Who holds me and loves me without question. Who seems so familiar to me for reasons I cannot fathom.
But he’s just a dream.
And I can’t sleep my life away.
When memories of a time long past begin to resurface, it takes everything I have not to do the unthinkable.
Because I love him. And I’m willing to do what it takes to get him back. Even fight the Devil.