I Want to Escape from Princess Lessons.

Leticia Dorman, daughter of a duke, is less than thrilled to be engaged to a crown prince. Betrothed since childhood and trained to be queen, she always hoped Prince Clarke would fall for someone else one day. So when he shows up at a ball with another woman, Lettie excitedly retreats to the countryside to start her new life—only for Clarke to appear, determined to win her heart.