• "Harry Potter" alum Matthew Lewis

"Harry Potter" alum Matthew Lewis (Photo : Twitter/Attitude)

Known for his "Harry Potter" role Neville Longbottom, Matthew Lewis, 25, recently showed off his sexy physique and bulge in a magazine, which J.K. Rowling, 49, apparently did not like.

"I will always support you whatever you want to do, Matthew," Rowling tweeted. "Now go put some clothes on."

Like Us on Facebook

Wearing only swimwear and underwear, Lewis graced the cover of the Attitude magazine's June 2015 issue, in which he talked about his physical transformation.

The last time Lewis was seen as Neville Longbottom was in the 2011 film "Harry Potter And The Deathly Hallows: Part 2."

"I was excited I guess to go on the red carpet on the release of the last film and be me, and not to have to have the fat suit under my t-shirt. It was quite an exciting buzz," Lewis told the magazine. "I was 21, I was like, 'Yeah, this'll be cool!' It was never meant to be a, 'Hey everyone, look at me!' but it was nice to be able to go and be myself.

Lewis added, "And then obviously a lot of attention focused on it, which I didn't expect at all. I've never considered myself to be good-looking at all, just average."

From 2013 to 2015, Lewis starred in the TV series "Bluestone 42." He is also set to star in the 2016 film "Me Before You" with Emilia Clarke, Sam Claflin, Charles Dance, Jenna Coleman, Vanessa Kirby, Janet McTeer and Brendan Coyle, among others.

Meanwhile, Rowling is currently writing the script of the Harry Potter' spin-off movie "Fantastic Beasts and Where to Find Them," according to Mirror