The 20-year-old pop star has admitted that she and Simon bonded during the last series of X Factor and she was even able to open up to the notoriously critical music mogul about her rocky past and her tough life experiences.
Speaking to The Sun, Demi said: "I've been able to tell him things that I don't tell the public — about my personal experiences, my journey and what I've been through. He's been really, really cool about everything. Way deep down there, he's a good guy."
We didn't exactly have Simon down as a good listener!
However, Demi did also explain that although the mean exterior Simon portrays on television can be misunderstood, the British entrepreneur is still rather vain and insists on always wearing his sunglasses indoors.
And he also likes to tease Demi a lot.
The 'Heart Attack' songstress - who recently revealed that she is good friends with Cher Lloyd - made her US X Factor debut last year, alongside Simon, LA Reid and fellow new judge, Britney Spears.
Given that Britney was the newbie of the bunch too, she and Demi hit it off right away and the pair even found themselves growing closer due to similar difficulties they faced during their younger years.
in 2010, Demi entered a treatment facility to deal with "emotional and physical issues". She later admitted that she'd been suffering from bullying, self harm and bulimia and had even experienced a nervous breakdown.
Speaking about how her struggles helped her to find some common ground with Britney, she said: "We've definitely bonded, I think because we've been through the same stuff.
"We have kept in touch. Our mums have become super-close, which is really random. It's super-funny."
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