Books and magazines slamming South Korea are flying from the shelves of bookstores, and while some involved are happy with soaring sales, others in the industry worry about the trend.

One publication that cashed in was Takarajima, a monthly magazine, which ran a feature story ridiculing South Korea in its year-end edition in 2013.

"We sold more copies than normal," said Toru Miyagawa, editor-in-chief. In fact, the edition sold 30 percent more than usual.