i-13

Consisting of members from the ages of 12 to 18, they trained for two years before debuting on October 18, 2005 with their first album One More Time. They went on hiatus after the release of their album and disbanded without any official announcements in late 2007. In 2006, Chuk (Eunhye) debuted as an actress in the movie, Jenny, Juno.

Meanwhile, Oh (Ahn Jungyoon) went onto debut as a musical actress and is known better known by the stage name Eun Chaewon. On September 25, 2009, it was announced that three i-13 members Jin (Minjung), Ja (Jieun), and Sa (Gajin) would be starting a new group called JQT under GP Entertainment with one new member, Min Sun. Following JQT's disbandment, Jin (Minjung), Ja (Jieun) and Sa (Gajin) re-debuted in the five-member girl group, S the One, in March 2012.