Pross Gates Ward
Proserpina Gates first appears in Outcrossing as a widow in her 30s. Her daughter, Cammie, is about to go off to tutoring school. Pross runs the bookshop in True Eyeworth, a magical village in the north of the New Forest of about 200 people. She's become friends with Ferry Wright Pride since Ferry's arrival, and also knows a number of other people in town. She has brief appearances in both Outcrossing and Goblin Fruit as a friend to both Ferry and Geoffrey Carillon. They've known each other since their school days, and she is one of the few people to call him Geoffrey. (They were both in Owl House) (Octavian was dark-skinned, his family have recent intermarriage from Northern Africa, and Cammie is visibly mixed race.)
At the beginning of Magician's Hoard, Pross approaches The Research Society for assistance. The bookshop isn't a reliable enough income, so Pross has taken on some additional research projects. Instead of the professional welcome Pross expected, she's sent to meet with Ibis Ward, who clearly is the scapegoat of the organisation. She finds him intriguing, and more to the point he's willing to help. Their invvestigation leads them into a maze of intrigue, and she finds out some of his long-hidden secrets. They end the book with Pross visiting Ibis after he's settled in to teaching at Schola.
(Click on the title above to learn more about Pross's role in that book.)