The lady of the castle Aspetta Ventura in La Tavola Ritonda.
She suffered from leprosy and could only be cured by the blood of a royal virgin. In the quest to heal her, her knights bled hundreds of virgins, most of whom perished. She was finally cured by the blood of Agresizia, Perceval’s sister, who subsequently died.
She appears in the Vulgate Queste del Saint Graal but is unnamed.
See also
Castle of the Lepreous Lady | The Legend of King Arthur
Source
La Tavola Ritonda | 1325–1350