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The Potions master's lavishly appointed office in the dungeons — where the Slug Club meets for exclusive dinners, where Ron is nearly killed by poisoned mead, and where Slughorn hides the memory that could end the war.
Slughorn's office is an extension of his personality — warm, inviting, and designed to make you feel special enough to share your secrets. The Slug Club dinners happen here: carefully curated gatherings of students Slughorn considers promising, where he draws out their connections and talents over excellent food and flattery. Harry attends because Dumbledore needs him close to Slughorn. Hermione attends because she is brilliant. Ginny attends because her Bat-Bogey Hex impressed the old man. The office is also where Ron Weasley nearly dies. Slughorn opens a bottle of oak-matured mead — intended as a gift for Dumbledore but never delivered — and pours Ron a glass. The mead is poisoned. Ron collapses, foaming at the mouth. Harry grabs a bezoar from Slughorn's kit and forces it down Ron's throat. The poisoner was Draco Malfoy, and the mead was meant for Dumbledore. Beneath the hospitality and the photographs and the crystallized pineapple, Slughorn's office contains the most important secret in the war: the real memory of the night Tom Riddle asked about Horcruxes. Slughorn carries it like a stone in his chest, and every glass of mead is partly an attempt to wash the taste of guilt away.
A comfortable dungeon office furnished far more luxuriously than its predecessors. Velvet curtains, gleaming brass lamps, a roaring fire. Comfortable armchairs arranged for intimate gatherings. Bottles of mead, oak-matured, and other fine spirits on a sideboard. Crystallized pineapple in a bowl on the desk. Photographs of former students — famous Quidditch players, Ministry officials, journalists — covering every surface.
Also known as: Slughorn's office, Slughorn's Office, the Potions office