John Smith
John "Not-A-Vampire-At-All" Smith was formerly known as Count Vargo St Gruet von Vilinus and is not only a Black Ribboner but the President of the Ankh-Morpork League of Temperance. A reformed vampire at the most extreme, Smith makes every effort to conceal any signs of vampirism. Although it should be impossible to roll your W's, "John Smith" is able to, leading to sentences like "As Commander of the W-w-w-watch, Sir Samuel..."
Rumour has it that he's finding going "B-total" very hard, and with his manic smile, permanently sweaty face and bloodshot eyes, it's easy to believe...
He has a teacup with many holes in it, where he's inadvertently bitten it. He wears appalling home-knitted jumpers and smokes a pipe in the belief that this will help him blend in. It doesn't. He also collects bananas and creates models of human organs out of matchsticks because he believes that hobbies help make him more human. Again, they don't.
Annotation
In literature, another vampire who maintained the belief that hobbies make you more human was the young newcomer in Anne Rice's Vampire series novel Blood And Gold. This young, un-named vampire also proved the point that vampires tend to the insanely anally retentive by building, loving and maintaining one of the most complex and intricate model railway layouts known to man or vampire. As a moment of self-referential humour, Terry Pratchett might not have done better.