Tyrion Lannister is not given a very flattering description in the books. He's described as ugly with stubby legs, a jutting forehead with one green and one black eye, and a mixture of blond and black hair. Now I think it's safe to say that Peter Dinklage is a legit snack and would never ever be described as ugly. In the books, Tyrion loses most of his nose at the Battle of Blackwater and is left with a "hideous" scar across his face, rather than the honestly pretty sexy slash on his cheek in the series.