Duke by Day, Rogue by Night

the long version

Constance Danbury is desperate to escape an arranged marriage to a man twice her age. Her only hope is to board a merchantman bound for Spain to enlist her aunt's help. Her plans go awry when she's captured by pirates. Even more alarming, he'd traitorous body kings for the man returning her to England. Pushed into a marriage of convenience, she's caught between two men -- one owns her heart, the other is bent on stealing it.