The trio of novels by British writer E.L. James that has so far sold 32 million copies in the United States has spawned a legion of fans clamoring for anything and everything Grey-related. And businesses are aiming to meet that demand.

Manhattan sex shop Babeland co-founder Claire Cavanah said after the final book in the trilogy was released in the United States in January, customers "were asking for specific toys that they had read about," but when the trilogy was re-released in April, "the product sales started to really spike."

Since then Cavanah noticed a sevenfold increase in demand for a particular sex toy featured in a sex scene between the book's two main characters, the dominant Christian Grey and ingénue Anastasia Steele. Riding crops, restraints, blindfolds, and spanking powder have also been popular.

The store also sells special "Fifty Shades" kits and hosts "Fifty Shades"-themed workshops that teach the mostly female attendees how to use the sex toys, but Cavanah said that wasn't the only curiosity - "They also just want to get together and see each other."

Fans have also been offered "Fifty Shades"-themed fashions, accommodations, and more recently, an official music album.

"Fifty Shades of Grey: The Classical Album," featuring Bach and Chopin, is the only spin-off item James has so far endorsed.

Released by EMI with tracks James personally selected, it debuted at No. 1 on the U.S. classical charts in September. The album resulted after another "Fifty Shades" compilation series hit No. 1 in July on iTunes, said EMI Classics Vice President Wendy Ong, "and she (James) noticed, and we started talking."

Asked about the other spin-off products at the New York album launch, James told reporters, "All of this has been a huge shock to my system. If people want this stuff, why not? If we can get it out there to people, then ... that's a good thing."

"WUTHERING HEIGHTS" BONDAGE

Yet some eyebrows have been raised at other efforts by entrepreneurs, including one British hotel that replaced its nightstand Bibles with copies of "Fifty Shades," with the Damson Dene Hotel owner Jonathan Denby telling Reuters that the hotel wanted to provide "something that people actually want to read."

Even baby clothes have been subjected to the marketing blitz. One Toronto couple emblazoned baby onesies with sayings like "9 months ago my mommy read 50 Shades of Grey" and "All Mommy wanted was a night with Mr. Grey."

The feedback has been mixed, but seller Kyle Lawley said that he and his wife had been surprised by strong sales. "Some people say 'it's taboo, I'd never put my kid in that,' and others say it's clever, it's funny, it's humorous," he said.

Publishers are also looking to cash in on the trend. Penguin's "Diary of a Submissive: A Modern True Tale of Sexual Awakening," has been marketed by directly comparing it to "Fifty Shades", which was initially self-published on the Internet.

Other publishers, such as those of racier versions of literary classics such as "Jane Eyre", and "Sherlock Holmes", say the link is less transparent.

A new version of "Wuthering Heights" will be released in October featuring Catherine and Heathcliff engaging in bondage.

The books publisher, Total-E-Bound founder Claire Siemaszkiewicz, said James' series made it easier for sexed-up books to gain a market foothold, but dismissed criticism that the classics have been sullied, saying they have been brought "to a new generation of reader."

A "Fifty Shades" movie is also in the works, but James has vowed she will not write any more books for the series. Still, her next book should whet fiction fans' appetites.

"It's an erotic tale, yeah. That's all I'm going to say about it," she said coyly.

(Additional reporting by Alicia Powell, Editing by Christine Kearney and Richard Chang)

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