Kim Hyung In, previously known professionally as K and currently known as Seo Yu An, is a South Korean singer, dancer, entrepreneur, and former member of NOM (엔오엠) and TST (일급비밀, previously known as TOP SECRET).

He made his debut in September 2013 as NOM's charisma vocal with their first digital single, "Pretty Noona".
Unfortunately, the group struggled to promote their music, and KJ Music Entertainment (KJ 뮤직 엔터테인먼트; formerly known as JM Star Entertainment & JSL Company) decided to disband them in February 2016 after they placed 3 members (including him) in a newly created group.

He then re-debuted in January 2017 as TOP SECRET's lead vocalist with their first mini album, "Time's Up". The group changed their name the following year to TST but faced controversy with Kyeong Ha's legal charges later that same year. They were never able to gain a steady fanbase and presumably disbanded due to inactivity in early 2020.

He decided to enlist for his mandatory military service on March 21, 2019, and he was discharged on January 14, 2021. After serving, he decided to change his stage name to Seo Yu An.

He made his debut as a solo artist in April 2021 with the digital single "Missing You". He also opened a restaurant and launched his own brand called Mellow Wolf.

(Source: MyDramaList) Edit Biography