For an unknown reason the humanoid race from Kaldarhns suffer very low birthrates of females. This is one problem the Kaldarhns have. Complicating their low birthrate is that children can only be produced from a "truemate" union. This union is with a genetically compatible partner with which a Kaldarhn male will mate for life. Surprise, out of seven galaxies the warrior race of the Kaldharhns rule (yes, rule), Earth is the only planet they found genetically compatible women. Making agreements with the governments of earth in exchange for technology, the Kaldarhns require that all unattached females between the age of 18 and 35 register with a database. The warrior will search the database for their "truemate" which they will magically recognize on sight. Once a truemate is identified she literally has no choice as to whether to mate with him or not. But these guys are so hunky and alpha, the women eventually, even if stubborn, relent, melting into their alpha arms.
This is an especially difficult trope to write. Aside the forced mating aspect, which is always creepy in my book, juxtaposing Earth culture and an alien culture is difficult to make realistic. With this trope there is nearly always declarations on how the alien culture is superior or is made to feel fairy-tale like. This book is no exception. The only realistic part was the MC's decision to try to hide to avoid registering. After Karac shows up everything sweeps into tropeland, from Karac's single-minded pursuit of Ashley, and over the top jealousy, to her government sanctioned abduction, to in short order (a month) falling in love with Karac and mating with him.
Karac is one dimensional. Ashley a little less so, but still has those extremes of decision making we've come to expect of these types of books. (I will hide, oops, he found me, I guess I have choice but to go with him. Oh, even though he's taken me away from everyone I've ever known, and I might not ever see my family again, I'm falling in love with him.) It was difficult to get a sense of a real love relationship here, as their main form of communication was sarcastic jibes, and Ashley's anger with being confronted by omissions of information from her mate.
If you've only read a couple of these types of books it is an OK afternoon romp, but stacked against the body of these types of books it stands as average for the most part, boring for the rest.