The Perfect Duchess by Erica Taylor

Andrew Macalister, oft regarded as the Stone Duke of Bradstone, hates his annual birthday ball tradition. He dislikes facing those around him who only see him for his title, and has given up on a chance to live a normal life. That is, until he spots Lady Clara Masson across the ballroom. Clara’s twin sister is the woman who infamously jilted Andrew at the altar five years ago, but little does Clara know, Andrew had been smitten with her since childhood, and he finds her presence a ray of sunshine in a dreary dukedom.

When Clara’s life is threatened by her evil brother, Johnathan, Andrew must do the only thing he can think of to save her: propose marriage. Between Clara’s trust issues and Andrew’s battle with societal norms, two find romance under dangerous circumstances.