"Lady of Sin" by Madeline Hunter

This is a follow-up to "The Romantic" and tells the story of Charlotte, Baroness Mardenford, and Nathaniel Knightridge, a famed barrister.  The author uses the familiar romantic trope of two smart, sophisticated characters who do not like each other and can't seem to stop bickering.  Charlotte is the youngest of six siblings and has been a childless widow for six years.  Nathaniel is the youngest of five sons and wanted to be an actor, but his father forbade it.  Instead he has used the courtroom as his stage quite successfully.  One day he catches a glimpse of a street urchin who bears and uncanny resemblance to Charlotte's brother-in-law, the current Baron of Mardenford.  As secrets come to light about this child, Charlotte grapples with secrets of her own concerning a party where she concealed her identity and seduced Nathaniel.

This is another quick and enjoyable read from Hunter and is the end of her Seducer series.  The main reason I read it was to get a few more glimpses of the two lead characters from "The Romantic," which I did.  405 pages.