Anyone know what this book is called?

[HJ]

I think I may have read it. I think the man knew who she was before they spent the night together. Does that sound like the same book? If so I'll try to remember its details!

[Jean]

The Black Diamond

I just read the synopsis, not the book but could this be it?

[Kelly]

An Improper Wife by Tarah Scott - I haven't read it, but remembered seeing on Goodreads.