|Occupation||Witch, shop owner of Boffo Joke Shop|
|Physical appearance||Extremely ugly, hooked nose, copious warts|
|Children||sons: Derek Proust and Jack Proust|
|Books||I Shall Wear Midnight|
Mrs Eunice Proust is the Ankh-Morpork witch and the mother of Derek and Jack Proust. The stones from which her powers originated are the stones within the loam under Ankh-Morpork from which previous cities were constructed. (This is similar to the flint within the chalk that gives Tiffany her powers.)
Growing up, Mrs Proust was the daughter of the city's most talented hangman and ran errands for the warders of the Tanty. She is the owner of the Boffo Joke Shop, where many of the mountain witches get their supplies, and where Derek and Jack work. She is vastly ugly, with a hooked nose and many warts and blemishes. She bases the masks she creates at the shop on her own face. It is revealed that she met her husband at a dance with terrible lighting. They were married for twenty-five years until he died.
Mrs Proust is somewhat more blatant with her use of power than Tiffany or the mountain witches, including enchanting a window so that it throws stones back at people who throw stones at it. This shows she is a very talented witch and one with different beliefs from witches such as Granny Weatherwax. Mrs Proust first appears in I Shall Wear Midnight when Tiffany visits Boffo in search of a Dwarf workshop to repair her broom.
Mrs Proust also provides discreet medical services for Watchmen who are too embarrassed to go to Igor and don't want their mother to know. She also has an Arrangement with Captain Angua von Überwald with regard to treating her hardpad. No money is paid, nor do serviceable second-hand clothes or surplus foodstuffs change hands, as they would in Lancre or elsewhere. No: Mrs Proust is a city witch. Hers is a city barter, performing discreet personal favours in the Watch buys favours, if for example she is banged up in a cell with Tiffany Aching, accused of criminal damage and importing Feegles into the city. Commander Vimes turns a blind eye.
There is a street in Ankh called Prouts. A connection with the wider Proust family cannot be ruled out; witchcraft runs in families, names are matrilineal, and witches have a habit of making an impression.