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In the very first round, 'A Little Princess' battled against 'Terius' for a chance to move onto the next round. On this day, they collaborated to sing Clazziquai's "Romeo N Juliet" which melted the hearts of the entire audience as their soft vocals matched perfectly well with each other.

For 'A Little Princess', however, she was not able to get past 'Terius' and revealed her identity. When she took the mask off, the panel was shocked to see Oh My Girl's YooA from WM Entertainment stand on the stage singing Han Young Ae's "Rhinoceros"! The cast members watched completely stunned and eventually came to their senses to comment, "I got chills!", "YooA, you did so well!", "Unbelievable", and more. Despite being the main dancer of the girl group, YooA impressed everyone with her singing ability on this week's episode of 'Mask King'.

Did you know 'A Little Princess' was YooA?