The `Twilight` star admits he can`t understand why girls find him attractive, despite regularly appearing in lists of the world`s sexiest men, and is astonished he used to be booked for modelling assignments.
He said: "I feel like a cartoon character. I look like an idiot - one of my legs is slightly longer than the other.
"I was such a terrible model. I was really tall but still looked like a six-year-old."
The 23-year-old British actor admits that his insecurities make it difficult to cope with life as one of Hollywood-s hottest celebrities.
He said: "I`m unbearably self-conscious about stuff. I`m trying not to drown. I guess I`m not the type of guy cut out to do a franchise. I`m not much of a crowd person."
However, when Robert landed his role as vampire Edward Cullen in the `Twilight` franchise, director Catherine Hardwicke admits she had her work cut out in making him look attractive.
She told Vanity Fair magazine: "They called me up and they literally said, `Catherine, do you think you can make this guy look good?` So I said, `Here`s what I`m going to do. I`m going to get his hair back to a different colour, do a different style. He would work with a trainer from now on. My cinematographer is great with lighting. He will study the cheekbones, and I promise you, we`ll make the guy look good.`?"
Robert has previously said he doesn-t care about being praised for his looks.
Earlier this year he said: "The hottest actor stuff doesn`t really mean anything. You have a month maybe with all this heat and hype."