G-Friend's Yuju revealed that she didn't even tell her fellow members about her 'Mask King' appearance. Viewers of the show know that the identities of the participants aren't revealed until they're eliminated, and it seems Yuju was extra careful not to spoil anything.

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On the July 28th episode of MBC FM4U's 'Kim Shin Young's Noon Song of Hope', Yuju said, "I was surprised that I was invited to 'Mask King' too. To be honest, I kept it a secret from my members. The preparation time was short, but my members didn't even know the situation. I rented a small vocal practice room."

In other news, G-Friend are currently promoting "Me Gustas Tu". What did you think of Yuju on 'Mask King'?