[2] In 2011, she was a contestant on the singing competition program Superstar K3 (under her Korean name, Yoon Bitnara), and was eliminated during the rival mission.
[10] As a songwriter, her breakthrough was the song "Some", written for Soyou and Junggigo (featuring Lil Boi of Geeks), released in February 2014.
Esna wrote the song with her agency's CEO, Kim Do-hoon, and Min Yeon-jae, Xepy, Lil Boi and Junggigo.
[11][6] It spent six weeks at the top of the Billboard Korea K-Pop Hot 100, tying the all-time chart record.
Most of Esna's compositions are inspired by R&B, jazz and swing, including Wheesung and Gummy's "Special Love" and songs written for RBW's girl group Mamamoo.
[14] In March 2015, Esna and Seulong released the song "Destiny", for the soundtrack of the television drama Hogu's Love.
The song was written by Esna, with lyrics telling men to stop using cliché pick-up lines and treat women with respect.