ONF (short for On and Off) is a six-member South Korean boy band that debuted under WM Entertainment on August 3, 2017, and later signed with KI Entertainment in March 2026 to continue their career without disbanding [ONF concludes contracts with WM Entertainment, group activities to continue without disbandment, Boy band ONF signs contract with agency KI Entertainment]. Celebrated as a late 3rd-generation K-pop group, they feature a unique dual-subunit concept consisting of the vocal-centric ON Team (Hyojin, E-Tion, MK) and the performance-focused OFF Team (J-Us, Wyatt, Yuto). The group is widely nicknamed the "Masterpiece Restaurant" (명곡 맛집) by critics and fans alike due to their high-quality, unskippable discography produced primarily by MonoTree, which features signature upbeat tracks like their 2021 breakout anthem "Beautiful Beautiful" [ONF(온앤오프) - KBS WORLD TV 210312, SONG REVIEW: Beautiful Beautiful – ONF - KBopped].