Who is The Egregious Professor of Cruel and Unusual Geography from The Last Continent: A Discworld Novel and what is their importance?

The Egregious Professor of Cruel and Unusual Geography is an unnamed member of the faculty of Unseen University (UU), the Egregious Professor has an office with a window looking out onto Mono Island, a tropical paradise that exists 30,000 years in the past. His colleagues vaguely remember him as young, well-tanned, and having large ears. He seems never to be around. His book-lined office is crammed with piles of yellowing paperwork, categorized boxes of rocks and odd vestiges of the sea. Senior faculty members visit, hoping that he might know the location of the mythical last continent of Fourecks, where another colleague, Rincewind the Wizzard, is marooned.