Twilight actors 'wind each other up' while on set

Booboo Stewart and Alex Meraz play werewolves Seth and Paul

We've heard all about the Twilight vampires but what's it like to be a werewolf in the record-breaking franchise?

Newsbeat caught up with Alex Meraz and Booboo Stewart who play Paul and Seth to talk fan attention, bare chests and the whole painted-on-abs debate.

The third Twilight movie Eclipse has plenty of bare chest action from the wolf pack, led by Taylor Lautner, but things may not be quite what they seem.

Meraz has admitted that some of the abs are actually painted on: "I'm not shy about it.

"Hell yeah - if I'm going to be immortalised I better look good, paint on my abs."

In demand

There was a bit of an awkward pause when we asked him if Taylor Lautner had his painted on too: "Erm, I'm just speaking for myself, I'm being very diplomatic.

"I'm just speaking for myself - I demanded my abs be painted."

And it's not just lead actors Taylor Lautner and Robert Pattinson who get crazy attention from fans.

Meraz says the wolf pack are in demand from fans of all ages: "Some people have different boundaries and some really go above and beyond to really get the full wolf experience."

And that wolf experience means fans have very specific requests: "They always ask us to take our shirt off," admitted Meraz. "It's the craziest thing."

Sneaky fan

Stewart chips in: "One lady did the best. She said, 'Oh, so can you tell us if you have an inny or an outy (belly button) and can you show us?'

"That was the sneakiest way to say take your shirt off and we almost did."

Eclipse sees Pattinson and Lautner's characters continue to fight for Bella

Meraz reveals it's also a bit one-sided: "We have a wolf pack girl now and no one ever tells her to take her shirt off."

For the wolf pack there is a lot of running around in forests only wearing cut off jeans and trying to pretend they aren't freezing.

"Between takes you put your robe on and stand in front of the heater and try and warm up," says Stewart.

Meraz admits it was tougher to pretend this time round: "In New Moon, the wolf pack, we were eager to play ball.

"It was our first time, we were really excited. This time round it really seemed a little ridiculous.

"I'd look around and see guys with shirts off and painted-on abs and thought, 'This is so weird'."

On screen there is major rivalry between the vampires and the wolves, which they have to put aside in Eclipse to battle an army of newborn vampires.

Meraz admits there was banter between the two camps on set too.

He said: "Jackson Rathbone, who plays Jasper, was just finishing a scene as we were waiting to go on set.

"We were standing there with our tops off and he says, 'Oh, did a YMCA meeting end?'

"So then when our scene was over and Jasper was passing with a few other Cullens I was like, 'Is The Cure concert over then?'"