Son Ju-yeon (Hangul: 손주연), better known as Eunseo (은서), was born on May 27, 1998 (age 24) in Incheon, South Korea. She is the sub-vocalist and sub-dancer of the South Korean-Chinese girl group WJSN and is a member of its Joy Unit. Eunseo is also part of the most recent sub-unit WJSN THE BLACK.