Her Enemy Protector by Cindy Dees
Rules of engagement for Special Forces soldier Joe "Doc" Rodriguez's newest mission:
Rule 1: Remember that Carina Ferrare is the daughter of Charlie Squad's most dreaded enemy--Eduardo Ferrare--and he will stop at nothing to keep his daughter and kill her rescuers.
Rule 2: To rescue Carina you must marry her, share a bed with her and somehow still be able to think enough to get the two of you out of her father's house alive.
Rule 3: Forget everything you've ever believed about not falling in love with your work.