Tante Oscar is one of the dark-skinned Mayfairs, related closely to Merrick Mayfair, the witch and fledgling of Louis. Before Merrick is turned into a vampire, Oncle Vervain predicts it and shares his prediction with Tante Oscar. Tante Oscar often sees Louis walking through the French Quarter at night, killing off the riffraff. It is Tante Oscar who informs Rowan Mayfair about the existence of vampires and how her family is connected with them. She has a small apartment in the French Quarter and lives to be more than one hundred years old.
Tante Oscar appears in Merrick (2000). For more perspectives on Tante Oscar in the Vampire Chronicles, read the Alphabettery entries Louis de Pointe du Lac, Merrick Mayfair, Oncle Vervain, and Rowan Mayfair.