J.K. Rowling, the creator of Harry Potter and easily one of the most famous living authors, is a Chamillionaire fan. Maybe. At the very least, she’s familiar with his Grammy winning hit “Rollin’.” (Yes, it won the Grammy for Best Rap Performance by a Duo or Group in 2007.) Replying to a critical tweet, Rowling referenced the lyrics of “Rollin,” and even better, Chamillionaire spotted it and replied. See their exchange below.