Singer IU explained the reason the Sadako dance she did back in 2012 on 'Yoo Hee Yeol's Sketchbook'.

On the 100th episode special, Yoo Hee Yeol revealed past unseen footage of IU from May of last year. She was singing when her voice suddenly cracked. At the time, IU apologized, saying, "I'm sorry. I'm sorry." 

Her apology wasn't the strange thing, however. What was a little odd was when she suddenly broke into a 'Sadako dance'. Apparently, the singer was trying to make up for her little mistake, and the crowd absolutely loved it. 

Yoo Hee Yeol commented, "IU, you've matured into an adult, but you've also matured musically," while IU said, "I think of 'Sketchbook' first when it comes to my comebacks. It's a place I want to go even though I'm scared of it."

Check out IU's full clip above!

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