Oh fark gimme that Tark. Listen, if you decide that you are going to read a book called "Assigned a Mate" I feel like you know what you are signing up for. Do you want lots of explicit descriptions of sexual activity? This book provides! Do you want a paper thing plot filled with laughably bad characters whose only motivations are to fuck or be fucked? This book provides! Do you want to be able to read it in a few breezy sittings while chuckling to yourself about the insubstantiality of it all? This book provides.
I'm not going to argue that this is some work of great literary fiction, nor am I going to argue that it is arousing on any level. What it is - all it is - is a book about a lady getting banged by one very buff alien dude. If you don't want to read that, then don't read this book. I wish that the aliens were a bit more alien. Why not have them have crab claws for feet and purple chest hair or something? The premise is "what if in the future, earth agreed to send women away for breeding on other planets?". That sounds grossly misogynistic (maybe it is) but there simply isn't enough substance to this book to get upset about anything. It's like Star Trek but the horny dial got cranked up past maximum.
There are just enough odd little touches to make this book be a grade above totally generic. The main character is a curvy doctor who was framed for a murder she didn't commit! I like to think about the world building that the author must not have. Imagine the meetings that earth had with all these other planets where they are like "Okay. You can bang our babes. But only once we make sure that our babes are a compatible match. Now everybody sign this treaty!" So dumb. Thumbs up for me.