Ral's Woman by Laurann Dohner (2009) is a nice combination of science fiction and romance in a very quick read.
Ariel is a human woman taken captive by an alien race called the Anzons, who are desperately seeking another group of females who can mate with them for the preservation of their species. (Although not sympathetic in this book, I could easily see them serving as the focus of a future book in a positive light.) Since they aren't able to mate with Ariel/humans, she's given as a prize for the Zorns, also captured and serving as slaves for the Anzons.
Ral, leader of the group of enslaved Zorns, is the winner of the battle to determine who gets to have Ariel. Although not a situation Ariel would have chosen for herself, at least Ral treats her well.
The sex scenes are fairly graphic, though more of the "vanilla sex," meaning involving one man (Zorn, in this case) and one woman.
One generic complaint I have that seems to apply to every Ellora's Cave e-book I've read is the number of errors a decent proofreader could have prevented--sentences that don't make sense, simple typos, etc. That gets frustrating when, frankly, the e-book prices aren't significantly lower than buying a print copy. The least they could do is to pay for a professional proofreader for their e-books. Or is that just the English major inside of me asserting herself??
My overall rating of Ral's Woman is a B-.