It is "her beauty".
Geoffrey Chaucer’s The Prioress' Tale is from The Canterbury Tales. The General Preface names the prioress as Madame Eglantine, and portrays her immaculate social graces and caring ways. Her representation recommends she is likely in religious life as methods for social advancement, given her highborn conduct and misspoken French. She keeps up a secular way of life, including keeping lap pooches that she benefits over individuals, an extravagant rosary and brooch engraved with "Love vincit omnia"
