This is a lush, romantic story of a (retired) courtesan who falls in love with a younger man. And the man just happens to be England's current hero, having returned from three years in Africa bearing valuable scholarly research as well as a fortune in gold.
James has a brilliant academic career, and perhaps an earldom, ahead of him, but none of that will happen if he publicly takes up with Coco. As for Coco herself, she's become wealthy and entirely independent and has no desire to subject herself to a man's dominion.
The lead characters are engaging, although I must say that the villain was cartoonish and crumpled without putting up a fight. But the love story is deep and complex and ultimately very satisfying.