Devotees of magical boy wizard Harry Potter and his trusted cohorts Hermione and Ron might want to stop reading right about now: Over in Harry Potter author J.K. Rowling’s home in the United Kingdom, Fifty Shades of Grey by E.L. James has beaten out all seven books in the Harry series to become Amazon UK’s all-time bestselling book.

Yes, an erotic novel with steamy BDSM elements that is often called “mommy porn” has dethroned the fantastical wizarding world in an epic battle of popularity that also pits the two authors against each other.

And as of today, and James displaces Rowling as Amazon UK’s new best-selling writer — Fifty Shades beat the previous record holder Harry Potter and the Deathly Hallows by more than two books to one, says Reuters.

“If J.K. Rowling was the literary phenomenon of the last decade then E.L. James looks certain to take that mantle in the current decade,” Gordon Willoughby, EU Director of Kindle, said in a statement. “In just four months, E.L. James has become Amazon.co.uk’s biggest-selling author of all time which is truly remarkable when you consider that we’ve been selling books for almost 14 years.”

You read that right — Fifty Shades beat everyone else just by being on sale for four months. Harry Potter and the gang have been kicking it on Amazon for more than a decade and were popular with both kids and adults. That’s a lot of mommy customers drifting to the grey side.

Fifty Shades of Grey is James’ first book, and has caused a sensation wherever greedy readers can get their hands on it since its debut earlier this year. A hotel in England even replaced the Gideon Bibles in each room with a copy of the steamy novel.

Wizards, magic, Quidditch, impossibly rich and handsome men changing the life of a self-proclaimed naive mousy college student through rough sex— hey, it’s all fantasy anyway.

“Fifty Shades…” outsells Potter on Amazon UK [Reuters]

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