In September 2019, she left SM and exclusively signed with Steel Wool prior to the release of her 2020 extended play X.

In May 2021, she also signed with Ryce Entertainment for her activities in China following a successful stint as a mentor in survival show Produce Camp 2021.

During an episode of the group's reality show, Go f(x), Liu revealed that her parents initially had mixed feelings regarding her music career.

Labelmate Yuri of Girls' Generation performed a cover of Ciara's song "1, 2 Step" at their first concert, Into the New World, held on December 19 and 20, 2009 in Seoul and featured her as a rapper and dancer.

In June 2010, she was featured in the lead single of Taiwanese singer Danson Tang's third Mandarin-language studio album, The First Second.

[14] On June 6, 2014, she became a host of the KBS show, A Song for You with Kangin of Super Junior and Yook Sungjae of BTOB.

In the same year, she appeared in a 9-episode travel reality series, One Fine Day, with singer Ailee, who is a close friend of hers.

On December 31, Liu was confirmed as a cast member for the second female soldier special of MBC's Real Men.

[21] As a part of the SM Station project, Liu's solo single, "Borders", was released in March 2016.

[24] On April 15, 2018, Liu released her first English-language solo mixtape, Rogue Rouge, with six songs, free on SoundCloud.

[29] Five days later, she confirmed that she would continue forward with her Steel Wool Entertainment contract, and would release an album that she previously prepared with the label.

: the Mandarin version of "blue" featuring MaSiWei from Higher Brothers, and an English song called "Vegas"; along with music videos for each.

[34] On May 27, Liu and Steel Wool signed a partnership with Ryce Entertainment for her solo activities in China.