YU-KI is a Japanese pop singer and occasional voice actress, born Yūki Kitamura on December 19, 1966, in Ehime Prefecture, Japan. She is best known as the lead vocalist of the popular J-pop group TRF (formerly trf), which debuted in 1992 and achieved massive success under producer Tetsuya Komuro. Her career in the entertainment industry began in 1990 after participating in a television dance audition, which led to her involvement with the dance group ZOO before forming TRF.

Her foray into voice acting began with the 1997 animated film Elmer no Bōken: My Father's Dragon, an adaptation of the children's book My Father's Dragon. In this film, she voiced the lead role of the young boy, Elmer Elevator. This role marked her debut as a voice actor, and she also performed the film's opening theme song, dragons' dance, which was released as her first solo single. Her involvement in the project thus combined her primary career as a singer with her new role as a voice performer.

Following this debut, YU-KI's voice acting work has been infrequent. She returned to the role nearly a decade later, appearing in the 2006 television anime series Bakegyamon. In the series' twenty-ninth episode, she voiced the character Queen Mekira. Consistent with her first voice acting role, she also contributed the ending theme song for the series, her third solo single, Shiroi Tsuki.

Beyond these two confirmed voice roles in animation, YU-KI's performance work has extended to stage and musical theater. She starred in Japanese productions of Broadway musicals, including the Jonathan Larson work tick, tick... BOOM! in 2003 and the musical play Claudia in 2004 and 2005. Her career is primarily defined by her success as a recording artist and live performer, with her contributions to voice acting representing a smaller, notable facet of her broader work in the entertainment industry.