E.L. James' erotic "Fifty Shades" trilogy has been credited by Ann Summers, the sex store chain, for increasing sales of nipple clamps and other sex toys at its shops.

E.L. James' erotic "Fifty Shades" trilogy has been a source of good business of many. Obviously the author made heaps of money, but last year it was also reported that its publisher Random House was offering huge bonuses to all employees that have been with the company the year the book was published. That's not all! Now, Ann Summers, the sex store chain, has credited the bestselling trilogy for increasing sales of nipple clamps and other sex toys at its shops.

"Fifty Shades of Grey, like Sex and the City before it, has got women everywhere talking about sex and encouraged them to be more intimate, experimental and confident," said Jacqueline Gold, the chief executive.

According to a report by The Guardian, the sex chain also organizes Tupperware-style parties for women to buy lingerie and "adult accessories". Over the last year, sales of these products including nipple clamps have increased fifteenfold. Sex toy sales have also increased by double digits over the last year as more people try to replicate the lifestyle mentioned in James' novels.

"Fifty Shades" sold more than 65 million copies worldwide and also topped approximately all best-seller lists. Gold revealed that from the year to June 2012, profits doubled and sales are expected to reach approximately $226 million in 2013, which is 27 percent up from the from the $178 million the company made in the year to June 2011.

"Books of that kind have moved from the back of the bookshop into the window. I don't think it is all about Fifty Shades," Gold said.