This was a good sci-fi alien romance. It had some steam, but also some sweet moments as Callum and Pearl got to know each other. The way Callum looked was a bit different, but that didn't seem to bother Pearl. It gets 3.5 stars from me, rounded up to 4 stars.
I liked Callum a great deal, and loved that he was so careful with Pearl. He realized that her abusive marriage had left her with a fear of men, so he was willing to move slowly and gently with her. He realized that she wasn't actually afraid of him, but that her trauma caused physical reactions she couldn't control. He was attracted to her, but was willing to wait until she was ready for intimacy.
I liked Pearl, too, and thought her history of an abusive marriage was sad. She soon realized that Callum was different from her husband, though, and knew that he would never hurt her. I was glad when they fell in love, as they were perfect for each other.
Overall, I really liked this book. I did wish it had been a bit longer, to allow for more character development. I would have liked more backstory on both Callum and Pearl.
Other reviewers have noted that they dislike the covers on this book series, since they look like comic books. I'm not really a fan either -- but I suspect that was so that the alien men on the covers could look like they were described in the book. It would have been difficult, and possibly quite costly, to use actual male models and make them look like the aliens. I prefer comic book style covers to those where the models don't look like the descriptions of the characters in the books.
My rating system is below.
1 star -- Hated it, or did not finish. I usually only give this rating if some of the content is truly objectionable to me, like if one of the main characters does something really awful, and gets away with it.
2 stars -- Didn't like it. This rating usually means that I thought the writing wasn't very good, the editing was terrible, I didn't like the characters, or it had other major flaws.
3 stars -- I liked it, but had some minor issues with it. This rating means that there were minor editing issues, the story needed more character development, it was just too unrealistic, or had some other fairly minor issue. The majority of books I read get this rating – I do not consider it a bad rating.
4 stars -- I liked it a lot. This is a high rating for me, and I rarely give a higher one.
5 stars -- I loved it, and will probably read it again. Very few books are good enough to get this rating from me. The ones that do are usually classics.