The Headless Horseman
From Jenny Everywhere Wiki
The Headless Horseman was a fictional character, dimly-known to Briar.
Biography
As a Librarian
A Headless Horseman based on the fictional character was generated by the Interdimensional Library as one of its ‘Librarians’. Briar, Century Smith and Jenny Nowhere briefly crossed paths with him during their visit to the Library, alongside many other Librarians based on fictional characters. (PROSE: Century Smith and the Time Terror)