Hermione told Cho, "This seems to be something like an Aversion curse." Aversion curses involved carving runes into the skin of the victim to create an aversion to a specific object or idea. It was used to create fear or hatred in the victim towards a particular group or individual. Hermione believed that’s how Voldemort tortured him to get Malfoy to kill his parents – it was an ancient and sadistic curse, banned more than a thousand years ago. "But he didn’t seem to hate anything, so maybe it’s not it?"