"Warn me next time, for God's sake," Rowling Tweeted after seeing the photo spread

By Jacqueline Andriakos
Updated May 21, 2015 12:40 PM
Credit: Attitude

We’re looking back at our favorite moments in Harry Potter history, and its stars, ahead of the release of J.K. Rowling’s book Harry Potter and the Cursed Child, available for all Muggles on July 29.

Brace yourselves, Harry Potter fans. The when-did-Neville-Longbottom-get-so-hot saga just took a sexy new turn.

Matthew Lewis, 25, best known for his role as the timid Gryffindor student from J.K. Rowling‘s fantasy franchise, has popped up shirtless on the cover of Attitude magazine – with a nearly nude spread inside.

The actor showed off his transformation in the June issue of the British mag and talked about his intense preparation for his role as a triathlete in the film Me Before You, scheduled to hit theaters in June 2016.

“I spoke to the director and I said it’d be nice to get into the mind-set of someone like that, because he’s not drinking alcohol, he’s just eating salads all the time, and I was very interested to know where you go to in your mind to have that level of commitment,” Lewis told the magazine. “So I sort of gave up alcohol – I say sort of, I have given up alcohol.”

He also said that he’s off sugar and carbs in order to go the extra mile for the athletic role.

“I really wanted to see if I could stick to such a strict regime, and to really understand what it’s like to have a goal like that and really 110 percent go for it,” says Lewis, adding, “I ve always been a bit of a sports enthusiast anyway.”

While fans are drooling over his svelte body and washboard abs, one author out there would have liked a little notice before feasting her eyes on Lewis in his undies.

“Warn me next time, for God’s sake,” Rowling Tweeted on Thursday, to which Lewis responded, “Well, this is awkward.”

But all was forgiven! “I will always support you whatever you want to do, Matthew. Now go put some clothes on,” Rowling wrote.

Another Potter buddy wasn’t all that shocked to see Lewis snag such a fan base.

“Matt Lewis has been a very good-looking guy for a little while now,” Alfred Enoch, 26, who played fellow Gryffindor Dean Thomas, told PEOPLE earlier this month.

“Like the sun emerges from behind the clouds, I knew it, it wasn’t surprising,” he added.

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