Vulpus
Chapter 59
Image credit: here
Professor Vulpus is a former headmaster of Hogwarts School of Witchcraft and Wizardry. He was known for being relatively quiet as well as providing sly and witty remarks. Vulpus loved numbers and was a self-proclaimed master of arithmancy, eventually taking up a position at Hogwarts as the Arithmancy professor. He worked behind the scenes more than interacting with the students during his time as headmaster. Due to this, not much is really known about Vulpus other than he became headmaster after Elizabeth Burke and was succeeded by Everard. It was said that Burke was furious about her replacement due to Vulpus having a Muggle mother.
The portrait of Vulpus now hangs in the Headmaster's office along with several other portraits depicting former headmasters and headmistresses. When the headmaster needs advice, Vulpus tends to stay quiet and observe while the other portraits are debating. He waits until there is a pause in the conversation to slide in a short, witty remark. He can usually be found having a light conversation with one or two of the other former headmasters about arithmancy.