Lee Soo-jung

Crystal Yi (born 1993), known by the stage name Chai or her Korean name Lee Soo-jung, is a Korean-American singer-songwriter. She is best known for winning SBS's K-pop Star 5.

Career
In 2015–2016, Yi participated in the fifth season of the audition talent show K-pop Star. She finished in first place with a perfect score of 300 points and selected Antenna as her agency.

After winning the competition, she returned to Chicago to finish her senior year as an art major at the University of Illinois at Chicago. During this time, in February 2017, she self-released the single "Color You", featuring the Chicago-based duo Iris Temple. In April 2017, she released a music video for "Thirst Trap", a single she had originally released in 2015 prior to joining K-pop Star.

In September 2017, she took part in Antenna's label concert series With Antenna, which toured South Korea and the US. Later that year, she featured on the winter duet single "When You Fall" with Sam Kim. She released an OST for the drama Angel's Last Mission: Love in May 2019.

Yi made her official Korean debut with the single album Give and Take in June 2019. The album consisted of three songs: "Alright", which she co-produced with Sam Ock; the title track "Give and Take", featuring pH-1; and "Color You", featuring Sam Kim, a remake of her 2017 single. Her second single album, Gimme That, featured two songs produced by Colde and was released in February 2020.

Yi parted ways with Antenna in May 2021, after four years with the company. She signed to World Star Entertainment in July 2021.

As lead artist

 * "Thirst Trap" (2015)
 * "Color You" (feat. Iris Temple, 2017)
 * "Time's Up" (2021)
 * "Wondering" (2021)

Soundtrack appearances

 * "Oh My Angel" (Angel's Last Mission: Love, 2019)
 * "Gift" (Dali and Cocky Prince, 2021)

Collaborations

 * "Everything is Okay" (with Antenna artists, 2020)
 * "Our Christmas Wish for You" (with Antenna artists, 2020)
 * "Deserve Better" (with MRSHLL, 2021)

As featured artist

 * "When You Fall" (Sam Kim feat. Chai, 2018)
 * "God Be My Witness" (Uzuhan feat. Chai, 2019)

Album appearances

 * Lee Jin-ah with Sam Kim, Kwon Jin-ah, Jung Seung-hwan and Chai – "We Are" (Jinah Restaurant Full Course, 2018)
 * Lucid Fall feat. Chai – "Pit-a-pat" (Nowana, 2019)
 * Dolly Ave feat. Chai & Always Dime – "Try" (Sleep, 2021)