The sales of both have been bolstered by the surge in e-book publishing, which affords readers the privacy of their Kindles, Nooks, or other devices.
Erotic titles with racy covers are believed to sell better as e-books because the technology removes the embarrassment of toting them around in public – and the same may be true of spiritual titles, experts say. Book jackets covered in angels and rainbows may be equally uncomfortable for some people to read in public, says Mark Coker, founder of Smashwords.com, a publisher of self-published e-books.
(Image from Jesus Diaz' list of the worst book covers of all time.)
The Dish 