According to People magazine, this isn't the first time Sia has put it all out there. In early October, she posed with a bared breast with just a banana emoji giving her a little cover.
Sia might be willing to bare her body for the camera from time to time, but one thing she typically keeps private is her face. When she performs or appears in public, the “Chandelier” singer uses oversized wigs to hide her face from fans.
In a 2015 appearance on "The Ellen DeGeneres Show," she opened up about why she hides her face.
“So that I can go to Target and buy a hose if I want to, or [if] I find I am in very need of a restroom and I can’t find one, I could go by the side of the road, and no one would be following me with a camera trying to get ‘the shot,'” she joked.
DeGeneres tried to coax her friend to take off the wig in that appearance, but fans were let down when a dancing reindeer interrupted the special and kept Sia’s identity a secret.
Earlier this year, the singer did step out sans wig and in March, she was spotted at LAX without her trademark wig as she headed to Dubai for a performance.
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She also had a wig malfunction in the summer of 2016 when a gust of wind blew the wig up enough to reveal the singer's face.