Naofumi Iwatani, the protagonist of The Rising of the Shield Hero, is voiced by Kaito Ishikawa in the original Japanese version and by Billy Kametz in Season 1 of the English dub, later succeeded by Stephen Fu beginning with Season 2. Kaito Ishikawa’s performance became central to the anime’s emotional tone, capturing Naofumi’s transformation from betrayed outcast to determined protector.
Japanese Voice Actor: Kaito Ishikawa
Date of Birth
October 13, 1993
About Kaito
Kaito Ishikawa is one of the most prominent voice actors of his generation, known for voicing intelligent, emotionally restrained, and highly driven characters across anime, games, and film. His performance as Naofumi Iwatani helped establish The Rising of the Shield Hero as one of the defining modern isekai anime.
As Naofumi, Ishikawa delivers a layered performance that evolves throughout the series. Early episodes emphasize distrust, bitterness, and emotional exhaustion, while later arcs reveal a calmer and more compassionate side beneath Naofumi’s guarded personality.
In interviews, Ishikawa has discussed how he approached Naofumi’s emotional complexity, especially the balance between cynicism and reluctant kindness.
Hometown
Bunkyō, Tokyo, Japan
Career Highlights
Kaito Ishikawa began gaining widespread recognition in the early 2010s and quickly became known for major leading roles in action, sports, fantasy, and drama anime.
Some of his most notable performances include:
- Naofumi Iwatani — The Rising of the Shield Hero
- Tobio Kageyama — Haikyu!!
- Genos — One-Punch Man
- Tenya Iida — My Hero Academia
- Sakuta Azusagawa — Rascal Does Not Dream of Bunny Girl Senpai
- Nine — Terror in Resonance
- Nero — Devil May Cry (Japanese voice)
- Langris Vaude — Black Clover
- Kuki Urie — Tokyo Ghoul:re
- Jin Enjoji (Jiji) — Dandadan
His role as Naofumi is widely considered one of his signature performances because of the character’s long emotional arc and unusually dark protagonist journey for an isekai series.
Full Current Filmography
The following list reflects documented credits from publicly available sources and may not be exhaustive.
Anime Television
- The Rising of the Shield Hero — Naofumi Iwatani (2019–present)
- Haikyu!! — Tobio Kageyama (2014–2020)
- One-Punch Man — Genos (2015–present)
- My Hero Academia — Tenya Iida (2016–present)
- Rascal Does Not Dream of Bunny Girl Senpai — Sakuta Azusagawa (2018)
- Terror in Resonance — Nine (2014)
- Tokyo Ravens — Harutora Tsuchimikado (2013)
- Seraph of the End — Shihō Kimizuki (2015)
- Black Clover — Langris Vaude (2017–2021)
- Dandadan — Jin Enjoji (2024)
Anime Films
- Rascal Does Not Dream film series — Sakuta Azusagawa
- Haikyu!! The Dumpster Battle — Tobio Kageyama (2024)
- My Hero Academia film series — Tenya Iida
Video Games
- Devil May Cry 5 — Nero (Japanese voice)
- Genshin Impact — Additional Japanese voice work
- Ensemble Stars!! — Tsumugi Aoba
- Granblue Fantasy — Various characters
- Persona franchise collaborations — Various roles
Critical Reception
Kaito Ishikawa’s portrayal of Naofumi has received consistent praise from anime critics and fans alike. Many reviewers highlighted his ability to portray emotional exhaustion and distrust without losing the humanity of the character.
Naofumi’s gradual emotional recovery throughout the series depends heavily on subtle vocal performance, and Ishikawa’s restrained delivery became one of the anime’s defining strengths. His work during the darker early arcs is frequently cited as a major reason viewers connected so strongly with the character.
Our Sources
Behind The Voice Actors – Naofumi Iwatani cast listing (https://www.behindthevoiceactors.com/tv-shows/The-Rising-of-the-Shield-Hero/Naofumi-Iwatani/)
Wikipedia – Kaito Ishikawa biography and filmography (https://en.wikipedia.org/wiki/Kaito_Ishikawa)
Wikipedia – Naofumi Iwatani character page (https://en.wikipedia.org/wiki/Naofumi_Iwatani)
ComicBook.com interview with Kaito Ishikawa about Shield Hero Season 4 (https://comicbook.com/anime/news/the-rising-of-the-shield-hero-season-four-naofumi-voice-actor-producer-interview/)
Social Media
Official Agency Profile: https://stay-luck.com/talent/ishikawa-kaito/
English Voice Actor: Billy Kametz / Stephen Fu
Date of Birth
Billy Kametz — March 22, 1987
Stephen Fu — Public full birth date not widely documented.
About Billy
Billy Kametz was an American voice actor widely celebrated for his emotionally expressive performances across anime, video games, and animation. He voiced Naofumi Iwatani in Season 1 of The Rising of the Shield Hero, helping establish the English dub’s identity during the series’ explosive international popularity.
Kametz brought a grounded intensity to Naofumi, especially during the character’s darker early story arc involving betrayal, isolation, and distrust. His performance emphasized Naofumi’s emotional exhaustion while still allowing moments of warmth and reluctant compassion to emerge naturally.
Following Kametz’s passing in 2022 after a battle with colon cancer, the role was recast for future seasons.
About Stephen
Stephen Fu succeeded Billy Kametz as the English voice of Naofumi beginning with Season 2. Fu approached the role with clear respect for Kametz’s original performance while gradually making the character his own.
His portrayal maintains Naofumi’s calm determination and emotional restraint while adapting to the character’s more mature and leadership-oriented role in later seasons.
Stephen Fu is also known for a growing number of anime and game performances, quickly becoming one of the most recognizable newer voices in English dubbing.
Hometown
Billy Kametz — Pennsylvania, United States
Stephen Fu — Not publicly documented.
Career Highlights
Billy Kametz
Billy Kametz became one of the most respected English dub actors of his generation through leading roles in anime and major video game franchises.
Some of his most recognized performances include:
- Naofumi Iwatani — The Rising of the Shield Hero (Season 1)
- Josuke Higashikata — JoJo’s Bizarre Adventure: Diamond Is Unbreakable
- Ferdinand von Aegir — Fire Emblem: Three Houses
- Shinei Nouzen — 86 Eighty-Six
- Takuto Maruki — Persona 5 Royal
- Galo Thymos — Promare
- White Blood Cell U-1146 — Cells at Work!
Kametz became especially admired for his emotional realism and natural-sounding dialogue delivery.
Stephen Fu
Stephen Fu has rapidly built a strong reputation in anime and gaming through versatile lead and supporting performances.
Notable roles include:
- Naofumi Iwatani — The Rising of the Shield Hero (Season 2 onward)
- Weather Report — JoJo’s Bizarre Adventure: Stone Ocean
- Thorfinn (young) — Vinland Saga (Netflix dub)
- Lucien — Granblue Fantasy Versus: Rising
- Additional roles in Crunchyroll and game productions
His continuation of Naofumi’s role received positive reactions from fans who appreciated the respectful transition following Kametz’s death.
Full Current Filmography
The following lists reflect publicly documented credits and may not be exhaustive.
Billy Kametz Filmography
Anime Television
- The Rising of the Shield Hero — Naofumi Iwatani (Season 1)
- JoJo’s Bizarre Adventure: Diamond Is Unbreakable — Josuke Higashikata
- 86 Eighty-Six — Shinei Nouzen
- Cells at Work! — White Blood Cell U-1146
- Blue Exorcist — Renzo Shima
- Promare — Galo Thymos
- Boruto: Naruto Next Generations — Metal Lee
Video Games
- Fire Emblem: Three Houses — Ferdinand von Aegir
- Persona 5 Royal — Takuto Maruki
- Marvel’s Avengers — Additional Voices
- Genshin Impact — Additional Voices
Stephen Fu Filmography
Anime Television
- The Rising of the Shield Hero — Naofumi Iwatani (Season 2–present)
- JoJo’s Bizarre Adventure: Stone Ocean — Weather Report
- Vinland Saga (Netflix dub) — Young Thorfinn
- Mashle: Magic and Muscles — Additional Voices
- Tokyo Revengers — Additional Voices
Video Games
- Granblue Fantasy Versus: Rising — Lucien
- Street Fighter 6 — Additional Voices
- Mobile game and anime dub productions — Various roles
Critical Reception
Billy Kametz’s portrayal of Naofumi was widely praised for its emotional depth and authenticity. Critics and fans frequently highlighted how naturally he captured Naofumi’s bitterness, exhaustion, and eventual personal growth. His performance is often considered one of the strongest aspects of the first season’s English dub.
After Stephen Fu inherited the role, fan discussion focused heavily on how respectfully the transition was handled. Many viewers praised Fu for preserving Naofumi’s established tone while allowing the performance to evolve naturally alongside the character’s development.
Both actors have become closely associated with the role, representing different eras of The Rising of the Shield Hero’s English adaptation.
Our Sources
Behind The Voice Actors – Naofumi Iwatani cast listing (https://www.behindthevoiceactors.com/tv-shows/The-Rising-of-the-Shield-Hero/Naofumi-Iwatani/)
Anime News Network – Billy Kametz memorial coverage (https://www.animenewsnetwork.com/news/2022-06-11/voice-actor-billy-kametz-passes-away-due-to-colon-cancer/.186557)
Crunchyroll – Stephen Fu casting announcement for Shield Hero Season 2 (https://www.crunchyroll.com/news/latest/2022/7/26/stephen-fu-replaces-billy-kametz-as-naofumi-in-the-rising-of-the-shield-hero-season-2)
Wikipedia – Billy Kametz filmography (https://en.wikipedia.org/wiki/Billy_Kametz)
Wikipedia – Stephen Fu biography and credits (https://en.wikipedia.org/wiki/Stephen_Fu)
Social Media
Billy Kametz
Official Website: https://www.billykametz.com/
Stephen Fu
X / Twitter: https://x.com/That_Fu
Official Website: https://www.stephenfuvoice.com/
