Ser Jaime Lannister, the eldest son of Tywin Lannister is depicted as a tall and handsome young man. He is shown as a military man with great knowledge of sword fighting--as shown by defeating Ned Stark on one-on-one combat--and horse riding.Jaime Lannister, also known as the Kingslayer, is a knight who has vowed as the lord commander of the Kings guard--in order to protect king from any harm.
In the series, it is shown that Jaime and his twin sister Cersie had affairs going on between them. Although his sister is already married to the King he and his sister's affair hadn't stopped. It is somewhere said by Tyrion, his younger brother, about the two siblings affair.
