A Knight of the Round Table.
During the Grail Quest, he and two other knights were escorting a lady to her brother’s castle when they were set upon by ten of the lady’s enemies. Gansonais survived the battle, but his two companions were killed.
Tired and wounded, he happily passed the woman on to Perceval when the latter happened along.
Source
Post-Vulgate Queste del Saint Graal | 1230-1240