[4] In 2013, Yeonji graduated from Kyung Hee University with an unusually high GPA for an entertainment figure after having submitted a portfolio of musical arrangements and a thesis on the songs in which she had participated.

[5] Yeonji won awards in various singing and dancing talent contests[6] and was eventually scouted by the record label and management company GM (currently MBK Entertainment).

[10] In March 2013, Lee Jinsung of Monday Kiz announced through Twitter that he had collaborated on a duet song with Yeonji, which he described as "memorable because it was work with a pure person who loves music so much.

"[11][non-primary source needed] The song, "Hurting but Happy," was written and produced by Lee and released in March as a preview track from Monday Kiz's fifth LP album.

[12] Yeonji contributed the song "In My Eyes" to the SBS miniseries I Can Hear Your Voice (Korean: 너의 목소리가 들려; RR: Neoui Moksoriga Deulrye) in July 2013.