|"Is this all real? Or has this been happening inside my head?"
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Gravy is a sauce that is made from the juices that run naturally out of meat and vegetables during cooking. It is often used at various events, especially during Christmas. It was present at the Welcoming Feast and Christmas feast of 1991. Gravy was being used as part of fake protective potions that were supposed to provide the drinker with protection against the Death Eaters, but actually had no effect at best. It was also served during the Christmas lunch at The Burrow in 1996.