Who is Prof. Leonora Stern from Possession: A Romance and what is their importance?

Leonora Stern is a professor from Tallahassee. She is interested in editing Christabel LaMotte's letters, but has not gotten very far. Leonora is a very large and majestic woman in all directions. She has olive skin, an imposing nose, a full mouth with a hint of African ancestry, and shoulder length thick, black, wavy hair. Leonora has French Creole and Native American ancestry. She is divorced and has a 17 year old son named Danny from an affair with a hippie poet. She left the hippie for an Indian woman professor and has had a string of female lovers since. Leonora is a force to be reckoned with, but she is a good friend to Maud. She is present at the climax of the story when the final clue is read.