Appearance and Character Edit
Robar is handsome and courteous, but the company he keeps is 'young and foolish' according to Catelyn Stark. Robar is probably one of the best swordsmen in the Vale. Ser Hyle Hunt remarks that, while Brienne could have contended with the rash Emmon Cuy on a good day, she would have stood little chance against Robar.
A Clash of Kings Edit
He joins Renly's Kingsguard, because he is not in line to inherit and the glory of tournaments is not going to give him a future. Catelyn estimates his age as being in his early twenties. Ser Robar is guarding Renly's tent and comes in when he hears Brienne call out. Catelyn Stark persuades him that Brienne is innocent and he holds off the others, allowing them to escape.
Ser Loras Tyrell murders Ser Robar in a fit of rage for his failure to protect Renly and kill Brienne. Later, Loras regrets this, as Robar was his friend and he comes to believe that Stannis is responsible for Renly's death.