This is the girl group "5 GIRLS" (not sure) which was supposed to have debut back in 2007. This girl group consisted of now member of SECRET Hyo Seong, Wonder Girls member Yubin and After School member UEE along with two other girls.

They were under the agency Good Entertainment Media Group that guaranteed these girls to debut as a girl group back in 2007 but the agency went bankrupt after a sudden financial problem and the girl group which even haven't debuted disbanded and went separate ways.

These girls trained for 2 years under the agency and was part of the a documentary program on MTV.

source: Nate
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