Williams and Rowling's friendship has been in full force for the last few months, as the former Daily Show correspondent explained that they struck up a bond over Twitter several years ago, before Rowling invited her to hang out in London.
"She messaged me back, just like a bunch of stuff, and she was like, 'When's the next time you're going to be in London?' She's like, 'I promise I'm not this blabby after the fourth cocktail.'" Williams explained during her appearance on The Late Show With Stephen Colbert last week. "So here's a photo of me and JoJo. It's amazing."