Amish romance novels are one of the hottest new subgenres, accounting for 15 of the top 100 religious fiction titles sold by Barnes and Noble. The Wall Street Journal has more:
Most bonnet books are G-rated romances, often involving an Amish character who falls for an outsider. Publishers attribute the books' popularity to their pastoral settings and forbidden love scenarios à la Romeo and Juliet. Lately, the genre has expanded to include Amish thrillers and murder mysteries. Most of the authors are women. [...] The plot of [Cindy Woodsmall's] 2006 novel, "When the Heart Cries," revolves around Hannah, a young Amish woman who falls in love with a Mennonite and hides her plans to marry him from her strict parents. The lovers struggle to overcome the cultural divide, and actually kiss a couple of times in 326 pages: "His warm, gentle lips moved over hers, and she returned the favor, until Hannah thought they might both take flight right then and there. Finally desperate for air, they parted."
(Hat tip: Emily Farris)