Lady of Sin — Madeline Hunter

She arrives at his home without warning or invitation, determined to win him to her campaign to reform women's rights. Instead, Charlotte, the widowed Baroness Mardenford, ends up being nearly seduced by Nathaniel Knightridge. No woman is safe from the mesmerizing sensual power of the famed courtroom advocate, and Charlotte discovers she is no exception. But does he recognize her as the masked woman who recklessly joined him in forbidden passion a month ago? And how to avoid becoming his Lady of Sin when he decides to pursue her again?