Dominic Monaghan had an unusual way of working out if he fancied a girl - he would insist she slap him across the face.

The star, 32, has been dating former Lost co-star Evangeline Lilly since 2004, and admits that when he was younger he used to enjoy rough antics - both in and outside the bedroom.

He says, "In my single days, a way for me to work out whether I was into a girl would be to ask her to slap me across the face. If it was rough, then I would be into it, but if it was a soft one, then I wasn't into her."

And the British actor discovered such kinky behavior would continue once he got the girl home: "There'd be a lot of slapping going on, a lot of scratching, biting, all that kind of stuff. But that's not really my thing now. As a young man you're a bit more self destructive. I was quite drunk when all this stuff was going on."

See more photos of Dominic here!

(This news article provided by World Entertainment News Network)

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