The Librarian

[close] The Librarian is a faculty member, and so he must have once been a human wizard. A strong wave of magic, altering reality, transformed the Librarian into an orang-utan; at that time, his colleagues still remembered how he looked as a human (The Light Fantastic). Back then, wizards were much too busy to help him get back to his original human form (although there is no record of his asking for help, either). After things settled down, the Librarian's colleagues found that he liked being an orang-utan, and fought all efforts to transform him back to human. The Librarian found out that opposable toes come in very handy when climbing up the book-shelves and sorting books. Also, a very large and strong orang-utan has more plausible arguments when talking about dog-ears and overrun return deadlines. Although the senior wizards looked very hard for one, there are no rules in the university constitution forbidding an orang-utan to be a member of the college council.
In appearance he has the rubber-sack-filled-with-water look of a well grown, 300lb male. He has not, however, developed the overlarge cheek pads that are a feature of the dominant male orang-utan, and this is because, as an ex-officio member of the University faculty he quite rightly regards the Archchancellor as the dominant male, even though most Archchancellors do not sit high up in trees with leaves on their heads.
Very soon, people forgot how the Librarian looked as a human, or what his given name was (though the latter is true for most other faculty members as well). This was helped along by the Librarian methodically removing, defacing or otherwise altering any and all photographs and records of his name in the University files. It is rumoured that the Librarian was once Dr Horace Worblehat, but no one utters this out loud. We do know however that he was born in Moon Pond Lane, Ankh-Morpork. Nowadays, only people very new to the University or Ankh-Morpork will find themselves surprised that there is an orang-utan in a University Library, or in a pub. Indeed, if someone were to point out that there is an orang-utan in the library, the wizards would probably ask the librarian if he had seen it.
All the Librarian ever utters is 'ook' or 'eek', but by now the wizards, and especially Rincewind, are so used to this that they understand the Librarian perfectly. They can even translate the merest 'ook' into full-fledged literary English sentences.
The Librarian is a member of the Librarians of Time and Space, and has the understanding of the power of L-Space, and has used these powers to appear at certain times to ensure the safety of particular books, bringing them home to his precious Library at UU.
During the events of The Last Continent, the Librarian's morphic field became highly unstable whilst he was suffering a severe cold. This instability manifested as a tendency, each time he sneezed, to transform into whatever shape best suited his immediate surroundings, e.g. a book ("The Story Of Ook"), a deck chair, a large penguin, a dolphin. Perhaps because his usual and preferred form as an orang-utan so suits his deeper nature, all such alternative shapes retained his luxurious coat of long red hair.