Devellyn isn't a happy man. Not only is he estranged from his family, he feels guilty for his brother's death
and as the icing on the cake he was robbed by the Black Angel and his humiliation is known all over London. He would feel better if only he could forget the pretty thief and stop lusting after her. And then he meets Sidonie, another woman that enchants him.
Sidonie is the Black Angel, trying to help women that were abused. Although a thief, she is honourable and when she realizes that she misjudged Devellyn she returns the stuff she stole from him. She is torn, she knows that he will react badly when he learns the truth, but she can't help but fall in love with him.
I love Devellyn. He reminds me a little of Dain (Lord of Scoundrels) who is one of my favourite heroes ever. Devellyn reaction to the truth did bother me a little, but the guilt he felt when his temper cooled made it better.
My only problem with the book is Sidonie's quest. She was acting incredibly foolish, I really don't understand what she hoped to accomplish. Stealing a few trinkets from a man can hardly be helpful to those he had wronged. But even if you can get over that, later in the book when Devellyn offers to give her money and find another way to help her she refuses. Come on, even a fool can see that that is the better way, that you can help more people. I know that there are more reasons for what she does, but still...
And since George Kemble is Sidonie's brother we learn more about him. The ones who read some books of Liz Carlyle will surely recognize the name. :-)