Roh Ji-sun is a South Korean singer and lyricist. She is a former member of the girl group fromis_9, formed through the reality survival show Idol School (2017). She left the group in 2024. Roh Ji-sun is a South Korean singer and lyricist. She is a former member of the girl group fromis_9, formed through the reality survival show Idol School (2017). She left the group in 2024.