Harry Potter spinoff author J.K. Rowling dished out her obsession with stiletto as she works on the screenplay for the new Warner Bros. film "Fantastic Beasts and Where to Find Them," which could include a cameo for Emma Watson.

J.K. Rowling, 48, spoke to MailOnline about her obsession with stilettos. "Naturally. I'm not a pumps girl, I'm not a sensible flats girl," she said.

True to her passion, she even took time off from working on the Harry Potter spinoff "Fantastic Beasts and Where to Find Them" and dedicated a line or two about the role of high heels in history and literature when she guest-edited a program for "Woman's Hour" on Radio 4.

She said high heels have come a long way from a "horse-riding aid" in the 18^thcentury to being a sex symbol today.

It was earlier reported by the New York Times that the Harry Potter Spinoff "Fantastic Beasts and Where to Find Them" has developed into a trilogy even if the original plan was for a one-off.

J.K. Rowling credited the persistence of Warner Bros. CEO Kevin Tsujihara for convincing her to extend the book into two films, that could include the cameo of Emma Watson.

"When I say he made Fantastic Beasts happen, it isn't P.R.-speak but the literal truth," J.K. Rowling told the Times. "We had one dinner, a follow-up telephone call, and then I got out the rough draft that I'd thought was going to be an interesting bit of memorabilia for my kids."

The book was originally published as a standalone in 2001 separate from the world of Hogwarts. It's about the book that Harry Potter and other freshmen in Hogwarts written by a magizoologist Newt Scamander. A magizoologist, said popcrush.com, is a scholar who studies magical creatures.

Emma Watson, when asked by MTV whether she's interested in appearing in the Harry Potter spinoff, said, "I would definitely be up for a cameo."