Seo Dong Sung is a South Korean singer, musician, former member of HONEYST (허니스트) and current member of N.FLYING (엔플라잉). He graduated from Unjeong High School.

He first appeared on TV as a trainee in the reality show by FNC Entertainment (FNC엔터테인먼트) called "Cheongdamdong 111". He was the bassist of KOKOMA BAND (꼬꼬마 밴드) alongside actor Kwak Dong Yeon, former KNK member Oh Hee Jun (now known professionally as Woo Je Yeon) and Omega X member Lee Hwi Chan.

Then he was introduced as the leader and member of NEOZ BAND through the survival show "d.o.b. (dance or band)". They competed against the trainees in team NEOZ DANCE (later debuting as SF9) for the chance to debut as a group, eventually losing to them after the public voting. However, FNC announced that NEOZ BAND will also get to debut under a new name.

He finally made his debut in May 2017 as HONEYST's leader, vocalist and bassist with their first single album, "Like You". However, creative differences between the members and between them and FNC began emerging, leading to their disbandment in April 2019.

He joined N.FLYING in the summer of 2019 as a guest member and appeared in several concerts. He made his official re-debut in January 2020 as the band's new vocalist, bassist and maknae but did not release any material with the band until June of that year with their seventh mini-album, "So, Communication". The band had previously debuted in Japan in 2013 and in South Korea in 2015, but FNC decided to add him after HONEYST disbandment.

He enlisted for his mandatory military service on May 8, 2023, and was discharged on November 7, 2024.

(Source: MyDramaList) Edit Biography