Royal Mistake by Cami Checketts

A too-confident American military hero, a sweetheart of a princess, and their forbidden love story.

Stuart has never accepted help or love from anyone and he isn’t about to grovel for either from the angelic princess everyone on Magna adores. His head knows she’s out of his league, but his heart has other ideas. With his Army Ranger background, Stuart is strong enough to stop kissing Belle and definitely strong enough to not fall in love with her.
When they are forced to spend time alone with angry dissenters surrounding them, will Belle’s perfect mixture of sweetness and determination overcome Stuart’s hard heart, or will he be able to resist the only woman he’s ever loved?