Diane Gaston 
Chivalrous Captain, Rebel Mistress [EPUB ebook] 

Duty was his only mistress, until he fell in love with his enemy… Amid the chaos of Waterloo, Captain Allan Landon stumbles upon a young boy. When long golden hair tumbles down, Allan’s faced with the most beautiful woman he’s ever seen. She reminds him of what he’s fighting for, and he silently vows to protect Miss Marian Pallant above all else.Back in London, the battle may be won, but Allan and Marian are now on opposing sides of a different war… As Marian’s enemy, Allan has three options: to fight her, to bed her or to unconventionally wed her!