Demi Lovato to be judge on 'X Factor' for a second season LOS ANGELES, March 28 (UPI) -- Fox says Demi Lovato has signed on as a judge for a second season of the American talent show "The X Factor." "I couldn't be happier that Demi wants to come back this year," judge and producer Simon Cowell said in a statement to EW.com Thursday. She's a superstar in her own right and was a fantastic mentor last year. Even though she can be really, really annoying -- I truly enjoyed working with her and so did the artists. I'm especially pleased she's back even during her world tour. "I am so excited to return as a judge and mentor on 'The X Factor,'" said Lovato. Last season was an unbelievable experience and I really enjoyed developing personal relationships with the contestants and the panel. I look forward to taking my previous experience and applying it to make this season even better. Lovato and Cowell served alongside L.A. Reid and Britney Spears on the judges' panel last season, however, Reid and Spears have both said they won't be back next season. Their replacements have not been announced yet.