On May 4, actress Kang Ye Won posted photos on social media of the 'Unnies' on set, looking like an actual girl group as they wore matching denim outfits and made cute�and sassy gestures.

The staff commented, "We wanted to emphasize on the concept of passion and youth, thus decided to go with white and denim with hints of red," describing the color coordination.

SEE ALSO: Min Hee Jin claims BTS, TWS, and RIIZE copied her Concepts

Meanwhile, the 'Unnies' will be officially making their debut on KBS 'Music Bank' with song "Right?" on May 12!