Madam Irma Pince is the stern and formidable Librarian at Hogwarts School of Witchcraft and Wizardry. Fiercely protective of her books and an unyielding enforcer of library rules, she serves as a recurring authority figure and obstacle for students throughout the series. Her allegiance is to Hogwarts and, most specifically, to the preservation of the Hogwarts Library and its collection. Madam Pince is characterized by her severe demeanor and her deep suspicion of anyone she believes might damage the books under her care.
Madam Pince's life before or after her tenure at Hogwarts is not detailed in the novels. She is present as the Librarian from the start of Harry Potter's first year. In Harry's first year, she refuses to let him borrow Quidditch Through the Ages from the library, stating it is a reference book only. In his second year, she is described as looking like an “underfed vulture” and reluctantly grants Harry Potter and Ron Weasley access to the Restricted Section after they present a signed note from Professor Gilderoy Lockhart. She is deeply suspicious of their motives for wanting the book Moste Potente Potions. Throughout the series, Madam Pince is a constant presence in the library, swiftly punishing any students who make noise, eat, or otherwise disrespect the quiet, scholarly atmosphere. She becomes particularly incensed during Harry Potter's fourth year when the library is crowded with students researching for the Triwizard Tournament, chiding them for their noise levels and confiscating snacks. During Harry's sixth year, she catches him with a book, Secrets of the Darkest Art, that he had transfigured to look like a different volume. She uses a spell to check the book's identity and is furious at the deception. Later, she confiscates Harry's personal, heavily annotated copy of Advanced Potion-Making, mistaking it for a defaced library book. It is only when Hermione Granger intervenes and explains that the book belongs to Harry that Madam Pince reluctantly returns it, still disgusted by the handwritten notes within it. A rare moment suggesting a softer side occurs at the funeral of Albus Dumbledore, where she is seen standing with Argus Filch, gently stroking his shoulder in a comforting manner. This implies a close personal relationship between the two similarly stern staff members. She is presumed to have fought alongside the other Hogwarts staff during the Battle of Hogwarts.
Madam Pince is described as a thin, irritable-looking woman. Her appearance is most memorably compared to that of an “underfed vulture.” Her personality is defined by her severe and territorial nature. She is the absolute ruler of her domain, the Hogwarts Library, and views students primarily as potential threats to the books. She has zero tolerance for noise, damage to books (including writing in them), or any breach of her rules. She is quick to anger and is viewed with a mixture of fear and annoyance by the student body. Despite her harsh exterior, her brief interaction with Argus Filch at Dumbledore's funeral suggests she may be capable of tenderness and affection, particularly towards those who share her love for strict order.
As a member of the Hogwarts staff, Madam Pince is a fully qualified Witch. While her combat abilities are unknown, she is proficient in charms relevant to her work.
While her personal possessions like her Wand are not described, her primary charge and domain is the Hogwarts Library. She treats every book within it as her personal property to be guarded at all costs.