Kokushibo in Demon Slayer: Kimetsu no Yaiba is voiced by Ryōtarō Okiayu in the Japanese version and Jonah Scott in the English dub. Both actors bring a commanding, measured gravity to the role of the Upper Rank One demon, with deep tones and restrained intensity that reflect Kokushibo’s ancient, tragic nature as a former Demon Slayer turned immortal swordsman.
Ryōtarō Okiayu (Japanese Voice Actor)
Date of Birth
November 17, 1969
About Ryōtarō
Ryōtarō Okiayu (置鮎 龍太郎) is a Japanese actor, voice actor, and singer born in Kitakyushu, Fukuoka, Japan. Affiliated with Aoni Production since the late 1980s, he has built one of the most recognizable voices in Japanese animation over a career spanning more than three decades. His natural vocal depth and ability to project quiet authority have made him a consistent choice for stoic, powerful, or aristocratic characters across a wide range of genres.
Okiayu made his professional debut in 1989 and rose to widespread recognition through his portrayal of Byakuya Kuchiki in Bleach and Kunimitsu Tezuka in The Prince of Tennis — both characters defined by composure and an almost severe sense of dignity, qualities that translate directly to his performance as Kokushibo. His vocal range (documented as A to E♯) and his Osaka-ben dialect background give his performances a distinctive texture that sets him apart from many of his contemporaries.
Beyond anime, Okiayu has maintained an extensive presence in video games, Japanese dubbing, and live-action work. He served as the Japanese dub voice for actors including Scott Foley and Taylor Kitsch, and has voiced major characters in franchises such as Mega Man X, Tekken, and Castlevania. He is married to fellow voice actress Ai Maeda. His casting as Kokushibo in Demon Slayer — first in the anime’s third season in 2023 and subsequently in the 2025 theatrical film — is widely regarded as a natural fit for the character’s ancient, sorrowful menace.
Hometown
Kitakyushu, Fukuoka, Japan
Career Highlights
- Kokushibo – Demon Slayer: Kimetsu no Yaiba
- Byakuya Kuchiki – Bleach
- Kunimitsu Tezuka – The Prince of Tennis
- Hisashi Mitsui – Slam Dunk
- Zero – Mega Man X
- Lee Chaolan – Tekken
- Shigure Sohma – Fruits Basket
- Treize Khushrenada – Mobile Suit Gundam Wing
Full Current Filmography
The following list reflects documented credits and may not be exhaustive.
Anime (Selected, Chronological Highlights)
- 1996 – Hell Teacher Nūbē — Meisuke Nueno
- 1996 – Mobile Suit Gundam Wing — Treize Khushrenada
- 1994–1996 – Slam Dunk — Hisashi Mitsui
- 1995 – Marmalade Boy — Yuu Matsuura
- 2001 – The Prince of Tennis — Kunimitsu Tezuka
- 2004 – Bleach — Byakuya Kuchiki
- 2012 – Toriko — Toriko
- 2019 – Fruits Basket — Shigure Sohma
- 2022 – Bleach: Thousand-Year Blood War — Byakuya Kuchiki
- 2022 – Ya Boy Kongming! — Zhuge Kongming
- 2022 – The Prince of Tennis II: U-17 World Cup — Kunimitsu Tezuka
- 2023 – Demon Slayer: Kimetsu no Yaiba — Kokushibo
- 2023 – Ao no Orchestra — Ryūjin Aono
- 2023 – Rurouni Kenshin — Hannya
- 2023 – Record of Ragnarok II — Hades
Video Games (Selected)
- Mega Man X series — Zero
- Tekken series — Lee Chaolan
- Castlevania series — Alucard / Genya Arikado
- 2025 – Demon Slayer: Kimetsu no Yaiba – The Movie: Infinity Castle — Kokushibo
Critical Reception
Okiayu’s portrayal of Kokushibo during Demon Slayer‘s Swordsmith Village arc was met with strong praise from both Japanese audiences and international fans watching with subtitles. His delivery captures the character’s duality — a demon of immense power carrying centuries of grief and rivalry — through controlled, low-register line readings that never veer into pantomime villainy. His performance is listed among his credited roles at MyAnimeList and has been noted by fans as a highlight of the arc’s voice cast.
Social Media
Ryōtarō Okiayu is active on X (Twitter) at @chikichikiko.
Jonah Scott (English Voice Actor)
Date of Birth
September 8, 1993
About Jonah
Jonah Scott is an American voice actor born in Villa Hills, Kentucky. He has been active in the industry since 2015 and has established himself as one of the more versatile English-language anime dubbing talents working today. He is perhaps best known for his lead role as Legoshi in Beastars, a performance that demonstrated his ability to portray complex, internally conflicted characters through nuanced vocal work — a skillset that translates well to a figure like Kokushibo.
Scott’s range extends from soft-spoken, introspective characters to intense, combat-focused roles, making him a flexible choice for antagonists and protagonists alike. His casting as Kokushibo in the English dub of Demon Slayer‘s third season in 2023 and his continued presence in the role in the 2025 video game The Hinokami Chronicles 2 and the theatrical film Infinity Castle reflect the confidence Aniplex’s dubbing team has placed in his ability to handle a pivotal villain role.
In addition to his anime work, Scott has built a strong presence in video game voice acting, with notable roles in the Dying Light franchise and Blue Lock. Born and raised in the United States, he has become a recognizable name among English-speaking anime fans in a relatively short period of time.
Hometown
Villa Hills, Kentucky, USA
Career Highlights
- Kokushibo – Demon Slayer: Kimetsu no Yaiba
- Legoshi – Beastars
- Sniper Mask – High-Rise Invasion
- Oliver Aiku – Blue Lock
- Joe – SK8 the Infinity
- Aoi Kaguragi – Kaiju No. 8
- Courier – Akudama Drive
Full Current Filmography
The following list reflects documented credits and may not be exhaustive.
Anime (Voice Acting)
- 2019–2026 – Beastars — Legoshi
- 2023 – Demon Slayer: Kimetsu no Yaiba (Season 3) — Kokushibo
- 2023 – The Misfit of Demon King Academy (Season 2) — Erdomaid DittiJohn
- 2023 – Tengoku Daimakyo — Juichi
- 2023 – Akuma-kun — Hiroki
- 2024 – Metallic Rouge — Afdal Bashar
- 2024 – Kaiju No. 8 — Aoi Kaguragi
- 2024 – Black Butler (Season 4) — Herman Greenhill
- 2024–2025 – Undead Unluck — Billy Alfred, Chikara’s Father
- 2024–2025 – Campfire Cooking in Another World with My Absurd Skill — Fel
- 2026 – Frieren: Beyond Journey’s End — Revolte
- 2026 – Ranma ½ — Kuno
Critical Reception
Scott’s English-language performance as Kokushibo has been well received among dub-watching fans of Demon Slayer, with many noting that his deep, measured delivery effectively conveys the character’s age, power, and underlying tragedy. His work on the role continued into the 2025 theatrical release Demon Slayer: Kimetsu no Yaiba Infinity Castle, further cementing his association with one of the series’ most formidable antagonists. His broader body of work can be explored on Wikipedia.
