Ko Yu Seon is a South Korean singer, actress, and former member of YEAR 7 CLASS 1 (칠학년일반). She graduated from Goyang Technical High School and later obtained an associate's degree in Aviation Service from Jeonghwa Arts University. She made her debut in 2014 (using the stage name Ko Eun Shil) as the girl group's dancer, rapper, and maknae with their 1st single, "Oppa Virus". The agency, DRB Entertainment (다른별엔터테인먼트), was not able to effectively promote the group and they quietly disbanded in 2018. She then ventured into acting and appeared as a reenactment actress in some episodes of seasons 2 and 3 of "Teenage Parents". (Source: MyDramaList) Watch drama online for free.