The Little Britain star began working with Cowell when they both appeared on the judging panel of U.K. TV show Britain’s Got Talent, which wrapped up last month (May12).
Walliams has now begun writing his fifth children’s book and reveals his most devious character was inspired by Cowell.
He says, “It’s about a little girl who befriends a rat and this one has a really evil villain in it, so he’s the one who wants to turn that rat into a burger.
“It’s based on someone who was on Britain’s Got Talent… and it’s not (fellow judges) Amanda Holden or Alesha Dixon.”
When asked whether his fictional bad guy could ever be as evil as Cowell, Walliams quipped, “I’d like to but it’s hard to outstrip reality.”