The Insider.com

The forthright Simon Cowell has been known to speak his mind as a talent show judge, and his comments are not only directed to the talent show contestants but also to his fellow judges. Cowell has found his bickering buddy in Demi Lovato this season on The X Factor, and while the two have been butting heads all season, things got especially rigid this week.

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Cowell, who particularly picked on fellow American Idol judge Paula Abdul (who also joined The X Factor for its first season) in his early days, is accustomed to the back-and-forth banter at the judges table. However, the 20-year-old Lovato is experiencing her first reality talent show judging gig.

RELATED: Demi Lovato Responds to Simon Calling Her a 'Brat'

"She was just in a particularly annoying mood, I think," Cowell assessed of this week's judges duel, "but I'm used to it."

While the two engage in some unapologetically sour banter during the show, they remain amicable off the show and were even posing for playful pictures at Thursday's red carpet viewing of the show. Lovato summed up the tension between in a short-but-telling admission.

"We're both on our periods," she said with a laugh.

VIDEO: Simon on Demi Scuffle: 'She Was Just Annoying'

After X Factor's judges exodus following its first season that cut Cheryl Cole, Nicole Scherzinger, and Paula Abdul from the show, it's unclear if Lovato or fellow new judge Britney Spears will return for Season 3. Cowell, also creator and executive producer of the show, made no decisive comment on the future judges.

"I never say [who will be judging next season] until the end of the season," he said. "Some want to [continue judging]; some don't want to. You never know."

Lovato, who also left her future as an X Factor judge an open question, will be a mere bystander on the rest of the show, as her mentorship ended Thursday with the elimination of her final contestant, CeCe Frey.

VIDEO: Simon: Britney is 'Very Tough to Please'

With two weeks remaining in the show, Cowell leads all with two out of the four remaining contestants, with Spears and L.A. Reid each left with one contestant in their respective categories.

Check out the full video above to hear the judges' reactions to the week's eliminations as well as their thoughts on pregnant Kate Middleton.