Навыки: Имитации, футбол, танцы хип-хоп
Кодзи Сето обнаружил свою заинтересованность в актреской деятельности, когда он увидел своего кумира Satoshi Tsumabuki в драме Orange Days (2004). После этого, в пятнадцать лет, его мать, зачислила его в местную Acting School Himawari в городе Fukuoka. Он получил свою первую роль после года обучения в комедии Rocket Boys. Он дебютировал как D-BOY в декабре 2005 года. Весной 2006 года, он переехал из своего родного города в префектуре Fukuoka, чтобы жить самостоятельно в Токио.

2015 - Gassoh
2014 - My Hawaiian Discovery
2014 - I Don't Have Many Friends
2013 - Judge
2013 - Sadako 3D 2 / Проклятие 3D 2
2012 - Sadako 3D / Проклятие 3D
2011 - Runway Beat / Ритм подиума
2010 - Rinne no Ame / Дождь возрождения
• 2010 - Kamen Rider × Kamen Rider Double & Decade: Movie War
• 2009 - Ju-On - Black Girl
• 2008 - Kamen Rider Kiva: King of the Castle in the Demon World
• 2008 - Shakariki
• 2008 - Kamen Rider Den-O & Kiva: Climax Deka
• 2007 - Tenshi ga Kureta Mono
• 2007 - Tonari no Yaoi-chan
• 2006 - Hit Parade

D-BOYS
• 2005 - 3rd D-Live (D-Boys-member only Live Entertainment Show)
• 2006 - 4th D-Live (D-Boys-member only Live Entertainment Show)
• 2006 - Yume no Kobako ni Ribbon wo Kakete ~Revised Edition~ ("Dream in a Ribbon Box" re-run)
TENIMYU: THE PRINCE OF TENNIS MUSICAL SERIES (as Eiji Kikumaru)
• The Prince of Tennis Musical: Advancement Match Rokkaku feat. Hyotei Gakuen (2006)
• The Prince of Tennis Musical: Absolute King Rikkai feat. Rokkaku ~ First Service (In Winter of 2006-2007)
• The Prince of Tennis Musical: Dream Live 4th (2007)
• The Prince of Tennis Musical: Dream Live 4th ~extra~ (2007)
• The Prince of Tennis Musical: Absolute King Rikkai feat. Rokkaku ~ Second Service (2007)
Гость не передачах:
• 2007 - Out of Order (Live Entertainment Stage Show) as Guest Star

Дискография
• 2006 - Tenimyu - Advancement Match Rokkaku feat. Hyotei Gakuen OST as Eiji Kikumaru
• 2006 - Tenimyu - Absolute King Rikkai feat. Rokkaku ~ First Service OST as Eiji Kikumaru
• 2007 - Happy Boys Image Collection 1 ~Yasashisa~ (Single as Kyoichi Segawa for Happy Boys)
• 2007 - Tenimyu - Dream Live 4th OST as Eiji Kikumaru
• 2007 - Tenimyu - Absolute King Rikkai feat. Rokkaku - Second Service OST as Eiji Kikumaru
• 2007 - Tenimyu - Best Actors Album 007 as Eiji Kikumaru (together with Shuichiro Oishi actor Yukihiro Takiguchi)
• 2007 - Tenimyu - Best Actors Album 010 Extra ~ 3rd Generation Seigaku ~ as Eiji Kikumaru
• 2008 - TETRA-FANG - Destiny's Play
• 2008 - TETRA-FANG - Individual System
• 2008 - Crimson-Fang - With You
• 2008 - TETRA-FANG - SUPERNOVA
• 2008 - TETRA-FANG - Root of the King
• 2008 - TETRA-FANG - Message [Tribute to Father]
• 2008 - TETRA-FANG - Silent Shout [Tribute to Dogga]
• 2008 - TETRA-FANG - Innocent Trap [Tribute to Basshaa]
• 2008 - TETRA-FANG - Shout in the Moonlight [Tribute to Garulu]
• 2008 - TETRA-FANG - Mind Garden
• 2008 - TETRA-FANG - No matter who You are
• 2008 - TETRA-FANG - Prayer~Message2

Официальные DVD
• 2006 - Tenimyu - Advancement Match Rokkaku feat. Hyotei Gakuen DVD as Eiji Kikumaru
• 2006 - DD-BOYS Volume 1 - 6 (+ 1 Special DVD)
• 2006 - Tenimyu - Absolute King Rikkai feat. Rokkaku ~ First Service DVD as Eiji Kikumaru
• 2007 - Prince Series DVD ~Koji Seto~
• 2007 - Tenimyu - Dream Live 4th DVD as Eiji Kikumaru
• 2007 - Happy Boys File 1 ~Kyoichi & Gen~
• 2007 - Happy Boys DVD Volume 1 - 4
• 2007 - Tonari no Yaoi-chan (DVD-only Movie)
• 2007 - Happy Boys File 2 ~Junta & Kokoro~
• 2007 - Happy Boys File 3 ~Kosuke~
• 2007 - D-Boys Stage Volume 1 ~Kanbai Gore~
• 2007 - Tenimyu - Absolute King Rikkai feat. Rokkaku - Second Service DVD as Eiji Kikumaru
• 2007 - Tenshi ga Kureta Mono DVD
• 2007 - Tenimyu - Supporter DVD Vol. 6 ~ Seigaku's 3rd Generation ~

Фотобуки, календари
• 2006 - D-BOYS Start!
• 2006 - D-BOYS Desktop Calendar ´07
• 2007 - Prince Series Photobook ~Koji Seto~
• 2007 - Happy Boys Bromide Set 1
• 2007 - Happy Boys Bromide Set 2
• 2007 - D-BOYS Stage Book Vol. 1
• 2007 - Prince Series Bromide Vol. 1
• 2007 - D-BOYS Desktop Calendar ´08

А так же:
• 2006 - DD-Boys DVD Event
• 2007 - Prince Series Photobook Event
• 2007 - Prince Series DVD Event
• 2007 - Prince Series Bromide Event
• 2007 - Happy Boys Image Album Event
• 2007 - 4 Tenimyu Best Actors Album Events
• 2007 - 2 Tonari no Yaoi-chan DVD Events
• 2008 - Kamen Rider Kiva Press Conference