Ever since Snape had the misfortune of falling victim to one of the Weasley twins' prank candies around Christmas, he had suffered from the side effects for a full week. He would occasionally feel the urge to stand in high places, hide in dark corners, or even groom his hair... It had tormented him for a long time.
Even though Snape went straight to Weasley's Wizard Wheezes the very next day and gave the two Weasleys a stern warning, Fred and George were unfazed.
More than a week later, the Weasley twins handed Alistair another piece of candy.
Chapter 469