While in middle school, Seyong was recruited as a trainee under JYP Entertainment in 2007, where he trained for three years.

The show featured his studies as a dance major in university as well as a visit from his high school friend, MBLAQ leader Seungho, who gave him advice and encouragement before his audition.

[13] Myname participated in reality show SBS MTV's Diary, which premiered on June 25, 2012.

[19] On January 7, 2013, Myname W Kitchen was premiered on Tokyo MX, a cooking show to introduce Korean food for Japanese audiences.

[22] The group successfully held their first solo Korean concert, The Beginning, on March 3, 2013 at the Interpark Art Center in Seoul.

[25][26] Myname's first mini album was digitally released on July 4 with title track "Baby I'm Sorry".

[30][31] Making their first performance on KBS' Music Bank on July 19, 2013, "Baby I'm Sorry" debuted at #5, the group's highest ever position on the countdown.

[32] On September 12, they made a guest appearance on Episode 8 of the Tooniverse mystery/children's series Thunderstruck Stationery.

The single album was produced by Lee Hyun Do of the legendary Korean hip hop duo Deux under the stage name D.O.

The film tells the story of five young Korean men from different paths of life who are scouted to take part in a potential K-Pop group from the Shin-Ōkubo neighborhood of Tokyo.

[42] The group also sang the theme song "Take Me to the Moon" for the Toei Company film Taekwondo Soul - Rebirth (テコンドー魂～REBIRTH) released February 15, 2014.

Along with #1 female idol winner, GI's OneKet, Seyong won an endorsement deal with DEMISODA which included a CF that also starred Insoo and Chaejin.

[50] "Stop The Time" was also chosen as the theme song for the NTV drama series Five Star Tourist.

[51] Myname released their fourth Korean single album with the title track "Just Tell Me" on May 13.

In August, a fan vote was initiated to determine the track list of a "best of" album entitled Mybestname!

The group held concerts in Germany, Sweden, Poland, Romania, Spain, Portugal, United Kingdom and France from September 1 to 11, 2016.

During promotions for the album release, member In-soo announced that he would be enlisting in the military for his mandatory service in the fall.

Myname released of their sixth Japanese album Kiseki with the lead single "Wiz" on July 25, 2018.

[62] In an interview with entertainment website Osen, Seyong denied the group's dissolution, noting their ongoing activities in Japan.