Credit: Amazon.com

The world can't get enough Fifty Shades of Grey, apparently. The smutty bestseller reached a milestone recently: It is now the fastest-selling paperback ever in the UK. Really.

According to the International Business Times, Fifty Shades, which was written by London-based novelist E.L. James, reached 550,000 pounds in sales faster than any paperback on record, and is only the fourth novel ever to sell 100,000 copies in a week in the UK.

Do you know what this news means? It means Fifty Shades of Grey is flying off the shelves faster than Harry Potter ever did in paperback. Is your mind blown? Because ours was.

Of course, you have to remember that we're talking paperbacks here. As anyone who lived through the Harry Potter craze knows, most fans bought the hardcover versions, which always came out well before the paperbacks. Fifty Shades of Grey hasn't come close to touching Harry Potter's speed of sale when you take hardcover into account. For example, Harry Potter and the Deathly Hallows sold 2.65 million copies in the UK in the first 24 hours alone.

Still, fastest-selling paperback ever is pretty good for a little novel that started out asTwilight fan-fic!

Source: International Business Times, Fox

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Rebecca Martin is an editor at Wetpaint Entertainment. Follow her on Twitter @BeccaMartin47.