'Harry Potter’s' Neville Longbottom – He's One Hot HuffleBUFF Now!

The little kid who became famous as Neville Longbottom from the 'Harry Potter' films is feeling the magic of a full body-bind curse -- 'cause Matthew Lewis is now a bonafide half-naked stud.

The 25-year-old stripped down to his Armani skivvies for a 10 page spread in Attitude magazine, where he’s almost unrecognizable from his old Gryffindork self.

Even 'Potter' author J.K. Rowling weighed in on Lewis' transformation, saying ... "I will always support you whatever you want to do, Matthew. Now go put some clothes on."

Somewhere Hermione Granger is kicking herself.