Exy

Exy, born Chu So-jung, is the leader, main rapper, and a vocalist of the South Korean girl group WJSN (Cosmic Girls). Beyond performing, she has become one of the group’s most active songwriters, penning lyrics for WJSN’s own releases as well as tracks for labelmates and other K-pop artists.

Early Life

Exy was born on November 6, 1995, in Busan, South Korea. She later attended Dongduk Women’s University, graduating in August 2020 alongside groupmate Soobin. Before joining WJSN, Exy trained as a vocalist, but a bout of vocal nodules during her trainee years pushed her to pivot toward rap — a switch that ultimately shaped her role as the group’s main rapper and leader.

Pre-Debut and Debut

In 2015, Exy appeared on the competitive reality show Unpretty Rapstar 2 and released two solo pre-debut singles, “쓸어버려” with Crucial Star and “Gettin’ Em.” She was revealed as part of WJSN’s Sweet Unit on December 24, 2015, and debuted with the full group on February 25, 2016, via the mini-album Would You Like?.

Songwriting Career

Exy has quietly become one of WJSN’s key in-house writers. Starting with “Thawing” on Dream Your Dream (2018), she has co-written numerous WJSN tracks, including “You&I” on WJ Please?, “Don’t Touch” on As You Wish, “Tra-la” on Neverland, and “Yalla” on Unnatural. Her songwriting has extended beyond WJSN too, with contributions to tracks for Cravity, The Boyz, Ive, Illit, and more — a rare crossover for an idol known primarily for rapping and performing.

Broadcast and Acting Work

Exy is a familiar face on Korean variety and competition shows, having appeared multiple times on King of Mask Singer, the rap survival show The Second World (2022), and the reality series Cabin Crew. Her acting credits include the 2021 JTBC drama Idol: The Coup, a cameo in Marry You (2024), and a role in The Divorce Insurance (2025). In 2021, she became a member of WJSN’s vocal sub-unit WJSN The Black alongside SeolA, Bona, and Eunseo.

Personality and Leadership

As WJSN’s leader, Exy is often the one speaking on behalf of the group in interviews and handling schedules behind the scenes. Her rap style is known for being punchy and confident, contrasting with a warm, easy-going personality offstage. Fans and fellow members often highlight her versatility — moving comfortably between writing, rapping, hosting, and acting — as one of the reasons she has stayed such a steady presence throughout WJSN’s decade-long run.