The Cherry-Stones of Oxford — Lorna Pearson

In late Victorian Oxford, two mismatched undergraduate friends uncover traces of worlds usually unseen: the dubious spirit-world of the traditional college ghost, the undiscussed secrets of student life after college gates are closed for the night, and the underworld of the town's slums, home of social classes living ghostly existences on the borders of the system. Inevitably they also discover the faultlines in their own friendship. A study of class, sex, crime and the fine arts in an ancient university town.