Kim Se-jeong, known mononymously as Sejeong, is a South Korean singer and actress. She finished second in Mnet's girl group survival show Produce 101, becoming a member of the project girl group I.O.I. She was also a member of Jellyfish Entertainment's girl group Gugudan. She is currently active as a solo artist and actress, best known for her lead roles in the television series School 2017, The Uncanny Counter, and Business Proposal.