Cast & creator
Koji Seki
Best known for JUJUTSU KAISEN, SPY x FAMILY, Frieren: Beyond Journey's End
Koji Seki (関 幸司, Seki Kōji, born November 25, 1982) is a Japanese voice actor from Saitama Prefecture who is affiliated with Raccoon Dog. He graduated from Pro-Fit Voice Actor Training School and joined the agency Pro-Fit. On April 1, 2022, he transferred to Raccoon Dog.
Also known as: Kouji Seki, 関 幸司, Kōji Seki
4
film credits
67
television credits
71
2012–2026 · acting roles
7.9
average across scored titles
Signature credits
Known for
Across film & television
Filmography (71)
Showing 71 of 71 credits
JUJUTSU KAISEN
Fumi's Father (voice)
2020
SPY x FAMILY
Rahden (voice)
2022
Frieren: Beyond Journey's End
Villager (voice)
2023
Haikyu!!
Kai Akakura (voice)
2014
Sword Art Online
Technical Staff (voice)
2012Sword Art Online
Goblin (voice)
2012
March Comes In Like a Lion
Authorized Person 3 (voice)
2016
You and I Are Polar Opposites
Convenience Store Manager (voice)
2026
Mission: Yozakura Family
Detective (voice)
2024Mission: Yozakura Family
(voice)
2024Mission: Yozakura Family
Battalion member (voice)
2024
Dan Da Dan
TV Station Producer (voice)
2024Dan Da Dan
Male Client (voice)
2024Dan Da Dan
Male Teacher (voice)
2024
Tower of God
(voice)
2020
BLUE LOCK
Reporter B (voice)
2022
Yashahime: Princess Half-Demon
Thug (voice)
2020Yashahime: Princess Half-Demon
Official (voice)
2020Yashahime: Princess Half-Demon
Peddler (voice)
2020Yashahime: Princess Half-Demon
Guard (voice)
2020Yashahime: Princess Half-Demon
Old man (voice)
2020Yashahime: Princess Half-Demon
Chimimoryo (voice)
2020Yashahime: Princess Half-Demon
Villager (voice)
2020Yashahime: Princess Half-Demon
Peasant (voice)
2020Yashahime: Princess Half-Demon
Bird of Paradise (voice)
2020Yashahime: Princess Half-Demon
Subordinate (voice)
2020Yashahime: Princess Half-Demon
Townsfolk (voice)
2020Yashahime: Princess Half-Demon
Vassal (voice)
2020Yashahime: Princess Half-Demon
Fisherman (voice)
2020Yashahime: Princess Half-Demon
Demon (voice)
2020Yashahime: Princess Half-Demon
Rock Demon (voice)
2020Yashahime: Princess Half-Demon
Palanquin Carrier (voice)
2020Yashahime: Princess Half-Demon
Green ogre (voice)
2020Yashahime: Princess Half-Demon
Staff member (voice)
2020Yashahime: Princess Half-Demon
Yokai (voice)
2020Yashahime: Princess Half-Demon
Raccoon dog in Mamiana Island (voice)
2020
NieR:Automata Ver1.1a
Kingdom Citizen (voice)
2023NieR:Automata Ver1.1a
Machine Creature (voice)
2023
Star Wars: Visions
Eno's Father / Resistance Member (voice)
2021
The Quintessential Quintuplets
Teacher (voice)
2019The Quintessential Quintuplets
Homeroom Teacher (voice)
2019
Puniru Is a Kawaii Slime
Academic Researchers (voice)
2024Puniru Is a Kawaii Slime
Academic Researcher (voice)
2024
Orb: On the Movements of the Earth
Knight (voice)
2024
Akane-banashi
Chusuke Chuotei (voice)
2026
I've Been Killing Slimes for 300 Years and Maxed Out My Level
Store Customer E (voice)
2021
Summer Pockets
(voice)
2025
Catch Me at the Ballpark!
Kaiser (voice)
2025
I Got a Cheat Skill in Another World and Became Unrivaled in the Real World, Too
(voice)
2023
Star Wars: Visions Presents - The Ninth Jedi
Satellite Digger (voice)
2026Star Wars: Visions Presents - The Ninth Jedi
Eesha's Father (voice)
2026Star Wars: Visions Presents - The Ninth Jedi
Villager on Samaz (voice)
2026
Solo Camping for Two
Izakaya Manager (voice)
2025
Let This Grieving Soul Retire
Greg Zangief (voice)
2024
Daily Lives of High School Boys
Basketball Guy (voice)
2012Daily Lives of High School Boys
Boy B (voice)
2012
Inexpressive Kashiwada and Expressive Oota
Mathematics Teacher (voice)
2025
Remake Our Life!
(voice)
2021
ID: INVADED
Staff (voice)
2020
Super Cub
Clerk (voice)
2021
The Aristocrat's Otherworldly Adventure: Serving Gods Who Go Too Far
Sebas (voice)
2023
Tearmoon Empire
Priest (voice)
2023Tearmoon Empire
Man (voice)
2023Tearmoon Empire
Soldier (voice)
2023Tearmoon Empire
Merchant (voice)
2023
HAIKYU!! The Dumpster Battle
Patient (voice)
2024
Welcome to the Outcast's Restaurant!
Merchant (voice)
2025
Turkey! Time to Strike
Samurai (voice)
2025
Sword Art Online the Movie – Progressive – Scherzo of Deep Night
Naijan (voice)
2022
Umamusume: Pretty Derby - Beginning of a New Era
(voice)
2024
DAN DA DAN: First Encounter
TV Station Producer (voice)
2024