Ryosei Konishi (小西 遼生, Konishi Ryōsei) (born Hiroki Konishi (小西 大樹, Konishi Hiroki), February 20, 1982) is a Japanese actor and voice actor from Tokyo. He is best known for portraying Kouga Saejima / GARO in the GARO franchise. He is affiliated with Cube.[1]
Biography[]
1982–2002: Early Years & Pre-Career[]
Ryosei Konishi was born on February 20, 1982, in Tokyo, Japan. Prior to entering the entertainment industry, he lived a private life away from public attention. During his youth, he developed an interest in acting and stage performance, participating in school-related activities that laid the groundwork for his later career. These years are generally regarded as his pre-celebrity period.[2]
2003–2004: Entry Into Entertainment Industry[]
Konishi began his professional acting career in 2003 under his birth name, Hiroki Konishi (小西 大樹). His early work consisted primarily of stage performances and supporting roles in television dramas. During this period, he also undertook voice acting roles, gradually establishing himself within the entertainment industry through consistent appearances rather than immediate stardom.[3]
2005–2006: GARO & Beast of the Demon Night[]
In 2005, Konishi achieved widespread recognition after being cast as Kouga Saejima in the tokusatsu television series GARO. His portrayal of the stoic Makai Knight was praised for its physical presence and emotional restraint, and the role quickly became one of the defining performances of modern tokusatsu.
He reprised the role in GARO Special: Beast of the Demon Night (2006), further strengthening his association with the franchise during its formative years and solidifying his popularity among genre fans.[4]
2007–2010: Red Requiem & Career Expansion[]
In January 2007, Konishi officially changed his stage name from Hiroki Konishi to Ryosei Konishi, marking a transitional period in his career. Following the name change, he expanded his professional focus beyond tokusatsu into musical theatre, film, and a broader range of dramatic roles.
During this era, he appeared in major stage productions such as Les Misérables and The Light in the Piazza, gaining recognition for his vocal ability and stage presence. In 2010, he returned to the role of Kouga Saejima in the 3D theatrical film GARO: Red Requiem, which was promoted as a milestone entry in the franchise.[5]
2011–2014: Flash Knight & Theater Work[]
Konishi reprised his signature role once again in the television series Flash Knight (2011), concluding the primary arc of Kouga Saejima within the franchise. He also appeared in the film Lament of the Dark Dragon (2013), reinforcing his legacy as the original bearer of the GARO title.
Concurrently, his reputation as a musical theatre actor grew, with acclaimed performances in productions such as Next to Normal, Thrill Me, and Piaf. By this period, Konishi was widely regarded as a performer capable of sustaining parallel careers in television and theatre.[6]
2014–2016: Private Life & Paternal Absence[]
In the mid-2010s, Konishi was reported to have been in a relationship with actress Hiroko Sato, whom he met through professional activities connected to the GARO franchise. According to later interviews given by Sato, the relationship resulted in two pregnancies during this period; the first ended in abortion, while the second led to the birth of a son in 2015. At the time, the identity of the child’s father was not publicly disclosed, and the matter remained outside public discussion.[7]
2017–2024: Stage Career & Continued Activities[]
From the late 2010s onward, Konishi maintained a steady career centered largely on musical theatre, appearing in long-running and high-profile productions such as Frankenstein, Natasha, Pierre & the Great Comet of 1812, and GOYA. He continued to make television appearances and remained involved in franchise-related events, preserving a loyal fanbase across both stage and screen audiences.
2025: Paternity Disclosure & Ongoing Work[]
In 2025, actress Hiroko Sato publicly identified Konishi as the father of her son in interviews with Japanese media, stating that she had raised the child as a single mother and describing difficulties surrounding paternal acknowledgment. She alleged that Konishi had initially resisted acknowledging paternity before later discussions regarding responsibility took place. These disclosures attracted significant media attention and online discussion.[8][9]
As of this period, Konishi had not issued a detailed public statement addressing the claims. Despite the renewed public scrutiny, he has continued his professional activities in theatre, television, and film.
Filmography[]
Television[]
- Modoken Quill no Issho (2003) – Kouji
- Victory! Futto Girls no Seishun (2003) – Hiroshi
- GARO (2005) – Kouga Saejima (as Hiroki Konishi)
- GARO Special: Byakuya no Maju (2006) – Kouga Saejima (as Hiroki Konishi)
- Komyo ga Tsuji (2006) – Takenaka Kyuusaku
- LOVE GAME (2009) – Shinozaki
- GARO: Makai Senki (2011) – Kouga Saejima
- Doctor-X: Gekai Daimon Michiko (Season 4) (2016) – Yuta Yaotome (Episode 8)
- Kaseifu no Mitazono (Season 3) (2016) – Kousuke Tokuyama (Episode 3)
- The First Penguin (2022) – Narushi Hazama
Films[]
- Norio's Room (2004) – Toshio
- Luna Heights 2 (2006) – Runa
- Triple Complex Returns (2008) – Yusuke
- GARO: Red Requiem (2010) – Kouga Saejima
- GARO: Soukoku no Maryu (2013) – Kouga Saejima
- GARO: Gekkou no Tabibito (2019) – Kouga Saejima
- Beethoven's Falsification (2025) – TBD
Voice Acting[]
- School Rumble (2004) – Ōji Karasuma
- Sugar Sugar Rune (2005) – Pierre
- G-9 (2006) – 3-5-10 / Sa-go-juu
Theatre[]
- The Prince of Tennis Musical (2004) – Shinji Ibu
- Hunter × Hunter Play (2004) – Kuroro Lucifer
- Les Misérables (2007–2009) – Marius
- The Light in the Piazza (2007) – Fabrizio Naccarelli
- Dracula (2011) – Jonathan Harker
- Piaf (2013) – Charles Aznavour
- Next to Normal (2013) – Gabe Goodman
- Thrill Me (2014) – Richard Loeb
- Frankenstein (2017–2020) – Henry Clerval Dupre / Monster
- Natasha, Pierre & the Great Comet of 1812 (2019) – Anatole Kuragin
- GOYA (2021) – Francisco Goya
- Kingdom (2023) – Shou Bun Kun
- LUPIN (2023–2024) – Countess Cagliostro
- Bonnie & Clyde (2025) – Clyde Barrow
Video Games[]
- Dragon Quest Swords: The Masked Queen and the Tower of Mirrors (2009) – Dean
Trivia[]
- Originally performed under his real name, Hiroki Konishi, before adopting his current stage name in 2007.
- Best known for his portrayal of Kouga Saejima in the GARO franchise.
- Has an extensive background in musical theatre.
- Stands at 182 cm (approximately 6 ft).