SEUNGJUN is the leader of ONF’s OFF Team and a dancer and vocalist in the six-member group. He was previously known by the stage name J-US and has performed under the name Seungjun since January 2024.

His stage and performance work is an important part of ONF’s dual-team identity. He remained in the lineup through the move to KI Entertainment in March 2026, when the group retained its name and artistic identity.

Dancing, vocal performances and group songs are not categorized as an individually released solo album. No confirmed independent solo record is credited to this member in the current profile.

Seungjun, previously known as J-US, is associated with the group’s dance-focused OFF team and its sharply synchronized choreography. His stage-name history is noted so older performance credits can be followed accurately.