This is by far the most badass Kpop group I know of. They were most known and loved for their tomboy concept

GI debuted under SimTong Entertainment with the song Beatles in 2013. They started out with the five members Hayun, One Ket (Won Yeonsang), A Ram, Eunji and AI (Kim Nayeon).

The company announced they would be releasing another song with Because of You soon after their debut, but it was ultimately delayed due to scheduling issues. The new release date was set for August, 2013.

Three months later, the group came back with mini album Tremendous. They were planning on promoting Booshit, with Dok2, for this album, but the song was deemed unfit for broadcast and they had to choose another song to promote, Gi-Yeuk. It's why they officialy have two titles for this mini-album.

In June, 2014 A Ram was announced by the GI International Fanclub to have left the group. The company's first resposnse was to deny it, but they later confirmed her departure and announced the addition of a new member. Hayun later posted a photo of the group practicing with two new girls, who were suspected to be joining the group. Though in November the same year the company announced that Hayun had also decided to leave the group.

In February 2015, labelmate Delta from AlphaBat told fans GI would be coming back with their third single Echo on the 25th.

A day after the release, member One Ket filed for a contract nullification with the claim of poor management. The company fired back saying One Ket and A Ram breached their contracts. One Ket did leave the group and the company announced three new members: Dokyung, Ji Amin (Lim Bomin) and Heeso (Moon Jinsil).

With the new line-up, a new concept was also introduced. For Turning Turning the girls left behind the old boyish image and went for a sexy feminine image.

Fans were not amused. They claimed this was not GI and called for a name change of the group. They already got mad once when the original line-up was chosen as models for 94Street (a restaurant) and the CFs featured the girls in dresses.

In March of 2015, Eunji let fans know on Twitter she was no longer part of GI. Not long after, speculations were made that the group had disbanded all together.

After their disbandment Dokyung signed with Play K Entertainment where she was going to debut with L.U.X. L.U.X debuted in May of 2017, but disbanded shortly after, leaving Dokyung currently without a group.

Heeso went back to HEXE for awhile and debuted in AGirls, before she joined her current group Various for their comeback with Shadow.