1THE9 (Hangul: 원더나인) was a nine-member project group formed through MBC's survival program "Under Nineteen". The group consisted of Doyum, Jinsung, Taewoo, Yechan, Taekhyeon, Yongha, Sungwon, Seunghwan and Junseo. They debuted under MBK Entertainment on March 2019 with their debut album "XIX". After two years of promotions, 1THE9 officially disbanded.
Korean: 용하
Japanese: ヨンハ
Korean: 루이
Japanese: テウ
Korean: 승환
Japanese: スンファン
Korean: 예찬
Japanese: イェチャン
Korean: 준서
Japanese: ジュンセオ
Korean: 도염
Japanese: ドユム
Korean: 진성
Japanese: ジンソン
Korean: 택현
Japanese: テクヒョン
Korean: 성원
Japanese: ソンウォン