Foxes saw a fan pull his tooth out for her to autograph.
Foxes
The 26-year-old singer - whose real name is Louisa Rose Allen - admits some of her supporters have gone to extremes to impress her, even when she didn't want them to.
She said: "I was in Scotland once and a guy pulled his tooth out with pliers.
"He was like, 'Do you dare me to pull my tooth out?' and I was like, 'No, don't do it.' He said, 'I'm gonna do it.'
"He pulled his tooth out and got me to sign it."
Foxes will release her second album, 'All I Need', this month and admits it would likely have been finished earlier if she hadn't been asked to tour with Pharrell Williams.
She told NME magazine: "I was in the middle of writing it and I got a call.
"You don't really say no.
"Most of it got written when I was on tour."
And the 'Body Talk' singer was very impressed by Pharrell.
She said: "I was impressed because he was constantly making beats.
"Two seconds before he'd go on, he's be writing music. He doesn't stop."
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