Kōki Uchiyama is a Japanese actor and voice specialist who voices Rui in Demon Slayer: Kimetsu no Yaiba, the anime by studio Ufotable. An award-winning performer, he is known for roles across the Kingdom Hearts, My Hero Academia, and Jujutsu Kaisen franchises.
In Demon Slayer: Kimetsu no Yaiba, the series animated by Ufotable, Uchiyama lends his Japanese voice to Rui, one of the antagonists faced by the protagonists. The character fits comfortably within a body of work that has frequently placed him in memorable villain and antihero parts, a register in which he is widely recognized. By the time he took on Rui, Uchiyama had already established himself through high-profile roles in numerous popular franchises, and the assignment further demonstrated his range in portraying complex, menacing figures. The performance stands as one of several signature antagonist roles in a career marked by prominent appearances across major anime and video game properties.
Born on August 16, 1990, Uchiyama is a Japanese actor who concentrates on voice acting and is affiliated with the Himawari Theatre Group. His career, active since 2003, spans both anime and video games. In gaming he is well known as Roxas and Ventus in the Kingdom Hearts series and as Neku Sakuraba in The World Ends with You. His extensive anime credits include Yuu Otosaka in Charlotte, Kei Tsukishima in Haikyu!!, Tomura Shigaraki in My Hero Academia, Rei Suwa in Buddy Daddies, Meruem in Hunter × Hunter, Toge Inumaki in Jujutsu Kaisen, and Rin Itoshi in Blue Lock.

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Uchiyama's work has earned him formal recognition within the voice acting industry. He was named Best Male Rookie at the 5th Seiyu Awards, an honor acknowledging promising newcomers to the profession. He was later named one of the Best Voice Actors at the Tokyo Anime Award Festival in 2015. These accolades, combined with his prolific output across many of the era's most popular anime and video game titles, underscore his position as one of the prominent voice actors of his generation.
In Demon Slayer: Kimetsu no Yaiba, the Ufotable anime, he voices Rui. Beyond that series he is known for Roxas and Ventus in Kingdom Hearts, Tomura Shigaraki in My Hero Academia, and Toge Inumaki in Jujutsu Kaisen.
He is widely recognized for villain and antihero roles, including Rui in Demon Slayer: Kimetsu no Yaiba. He is also known for Neku Sakuraba in The World Ends with You and Meruem in Hunter × Hunter.
He lends his Japanese voice to Rui, one of the antagonists faced by the protagonists in Ufotable's Demon Slayer.
Yes. He was named Best Male Rookie at the 5th Seiyu Awards and was later named one of the Best Voice Actors at the Tokyo Anime Award Festival in 2015.
He is affiliated with the Himawari Theatre Group. Born on August 16, 1990, the Japanese voice actor has been active since 2003.
This content is original writing by Daddy Jim Headquarters based on the Demon Slayer anime series, manga, and official materials. Episode and chapter references are cited where applicable.
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