Fairly late on in the series, we learn that Voldemort has managed to cheat death by splitting up his soul and placing it into various objects, called Horcruxes. Unless all of these objects are found and destroyed, Voldemort pretty much can't be killed. So the question is, then: how did he do it? In the books, the only way to create a Horcrux is by killing someone in order to split your soul, but this theory argues that Voldemort completes this process through cannibalism. Throughout history (and in early, pagan superstition and ritual) cannibalism was associated with the act of essentially gaining other people's strength and power through consummation. The art of necromancy, then (of which Voldemort is a master) is the art of harnessing the dead for power. After all, Voldemort certainly wasn't personally responsible for the deaths of everyone who enabled his soul to be split. During the height of his power, Voldemort had a whole host of people to enact his bidding, specifically the Death Eaters. So how did Voldemort split his soul seven times if he didn't actually kill all seven people? Simple. He cast a necromantic spell on a physical piece of their flesh (or perhaps a large amount of their flesh) and ate it. This would explain why Hermione and Slughorn are so disgusted by the Horcrux process (a process that we the reader are never privy to). Not only that, but Rowling's editor at the time also expressed horror at this hidden detail, even though it never fully made it into the book.
