Miss Darby's Duenna

Sir Harry Hawthorne thought he was making a marriage of convenience to a childhood friend—until his fiancée captures the fancy of the dashing and dangerous Lord Mannerly. Suddenly Sir Harry’s jealousy is roused to the point that he assumes the identity of his reclusive grandmother in order to keep the all-too-grown-up Miss Olivia Darby under his watchful eye. Regency Romance by Sheri Cobb South; originally published by Prinny World Press