In late March 2013, T-ara's agency Core Contents Media were in the midst of forming a new unit from the group with the members Eunjung, Areum, Jiyeon and Hyomin.

[1] T-ara previously tried sub-units with the promotions of their sixth Japanese single "Bunny Style!

[2] T-ara N4's debut single, "Jeon Won Diary" (전원일기; Jeon-won Ilgi), was inspired by the 1980s South Korean drama of the same name.

[3] Produced by Duble Sidekick, the song is said to have "funky and intense" dance music combined with elements of hip-hop,[4] with the main motif of "Jeon Won Diary" about breaking away from the same everyday routine.

[3] T-ara made their first visit to the United States on May 12, 2013 to meet with several musicians and music industry insiders along with Chris Brown who discovered the group recently, liked its songs and style and suggested a collaboration single .