Sejeong (??) is a South Korean singer-songwriter and actress signed under Jellyfish Entertainment. After coming into prominence as the runner-up on the hit idol competition show "Produce 101," she debuted in 2016 as a solo artist and member of now-disbanded girl groups I.O.I and Gugudan. In 2017, she was cast in her first leading drama role in KBS's "School 2017."