[1] In 2012, she made her debut as a member of Spica under B2M Entertainment, the agency of Lee Hyori, with the single "Doggedly" released on January 10.

[2] Kim made her solo debut in October 2013 with "Crazy Girl"; Lee participated in its composition and production.

[7] In 2016, Kim released the main theme song "Our Story" for the series Piped Piper,[8] as well as "Miss You" for the soundtrack of The Royal Gambler.

[10] Later that year Kim appeared on JTBC's Girl Spirit, winning the contest program and receiving a new car.

[14] She also participated in the soundtrack for the series with cast members Park Ye-eun, Suran, and Kang Han-na.

[27][28] The musical made its Broadway debut at Circle in the Square Theatre, and closed two weeks into its run.

[29] Kim, with the stage name Ru.B, joined the hip-hop group Uptown under T Cask as a guest vocalist for their 25th anniversary best-of album Back II Analog in December 2023.

Her wedding was attended by the former Spica members as well as Park Jin-young, who sang a duet with her husband.