Washington, Mar 18 : Filming Quidditch scenes in the sixth Harry Potter movie is turning out to be a real pain in the butt for the young cast.

Actor Rupert Grint, who plays Harry's best friend Ron Weasly in the movie, reveals that sitting on a broomstick for hours has left them all with numb butts.

"You sit on a broomstick for hours and it starts to hurt. It gives you a numb bum," The Sun quoted him, as saying.

However, his bottom is not the only one that Grint is bothered about, for he recently got a good look at those of two streakers in Farnham, Surrey, where some key scenes were being shot.

"We had two streakers down there," he said.

The actor also revealed that the sixth movie 'Harry Potter and the Half-Blood Prince' is almost completed, and that the cast and crew will soon be starting work on the final adaptation that has been split into two movies.

"We'll be finished filming in a few months. Then we'll be making the final ever one. I think I'll miss it," he said.

"I'd like to do a comedy movie next but we'll have to see what comes up."