Priscilla Farnese, a priestess of the Order of the Crest who shared the family name of the late pope, possessed pink hair and green eyes. She wore a white headscarf, a white vest over her chest, and a long black vest reaching her feet, along with white gloves and boots. She wielded the unique three-dimensional Crest called the Holy Grail, distinct from those held by other Order members, which manifested visibly during her healing magic. Order teachings claimed gathering all Crests into the Holy Grail would summon a god to end the age of Chaos, a narrative paralleling the Grancrest's formation.

Earnest and steadfast, Priscilla frequently attempted to proselytize Theo Cornaro and Siluca Meletes about her Order's beliefs, remaining unoffended by Siluca's skepticism. During healing, she sometimes entered trance-like states, uttering prophetic insights, such as those concerning Irvin's fate after healing him or telling Aishela she was "not destined to die here." She joined Theo's cause early, hoping to aid him in what she saw as a divine battle against Chaos. This decision caused tension due to Siluca's reservations about the Order's rumored confiscation of Crests; Priscilla politely silenced discussion when Siluca inquired about a potential family connection.

Her story ended when the current Pope, under Pandora's influence, killed her. Unlike typical Crests formed from Chaos, her Holy Grail Crest did not dissolve into a black orb upon death. This anomaly fueled speculation that the Holy Grail originated from residual Cosmos remaining after Chaos was unleashed in Ataltan. Further theories suggested the Holy Grail, representing light, and the Grancrest, representing darkness and forged from Chaos, were counterparts; their fusion could achieve light-dark balance and purge Chaos from the world.