Jang Se Bin, known mononymously as Sebin, is a South Korean singer, dancer and former member of SNUPER and current member of OMEGA X. He graduated from Songwoo High School and later obtained a bachelor's degree in Applied Music from Daekyung University.

He made his debut in 2015 as SNUPER's rapper, vocalist, face of the group and maknae with their 1st EP, "Shall We". The group enjoyed some success at the beginning, but in early 2020, it went into an indefinite hiatus when some of the members began enlisting in the military.

While on hiatus, he re-debuted in July 2021 as a member of OMEGA X with their first single album, "Vamos". However, in October 2022, a video of the CEO of OMEGA X's (Spire Entertainment) label abusing him and his group members came to light. The members filed a lawsuit against their company to cancel their exclusive contracts and to file for the trademark of their group name. In January 2023, OMEGA X won the lawsuit and officially ended their contract with the agency. This was finally made official on May 8, 2023. Around the same time, Widmay Entertainment announced SNUPER's disbandment after the contracts of all members expired.

Since July 2023, OMEGA X have been represented by IPQ.