In the Post-Vulgate, a maiden of Guinevere’s service who led the newly-knighted Perceval from his seat at the Table of Less-Valued Knights to the seat adjoining the Round Table’s Perilous Seat, proclaiming it his own. She had been mute before this episode, and died (at her own request) soon afterwards.
The same sort of maiden appears unnamed in Chrétien de Troyes’s Perceval, as Cunneware in Wolfram von Eschenbach’s Parzival, and as Lede in Heinrich von dem Türlin’s Diu Crône. The scene is repeated in Malory, but the maiden is again unnamed.
In some tales of Lancelot, a similar “mute” maiden first speaks to Lancelot upon his arrival to Arthur’s court, foretelling his greatness.
Sources
Post-Vulgate Suite du Merlin | 1230-1240
La Tavola Ritonda | 1325–1350