Vienna Dawn (The Imperial Season #3)
Mary Lancaster

Resourcefully, Dunya secures Trelawny’s alliance in her master-plan to marry her first love. After all, having lost an arm and an affianced bride in rapid succession, the captain is clearly in need of her peculiar brand of help in his own affairs. Together, they embark upon a deception intended to win back their old loves.
Roused from indifference by Dunya’s whirlwind vitality, Trelawny adroitly handles his sham engagement, hostile family, wicked seducers, espionage, elopements, and duels, all the while protecting Dunya and trying very hard not to fall in love with her.
And Dunya begins to suspect that first love is not always the greatest love – or even the most fun.