Kousuke Kujirai is a Japanese actor, voice actor, and singer born on July 20, 1987, in Saitama Prefecture, Japan. His career in entertainment began at a young age, as he was exposed to performing arts through his mother, who was a teacher of traditional Japanese dance; he started performing on stage at the age of four. He later joined a theater troupe in his third year of middle school and was scouted by an entertainment agency while performing on stage during his first year of high school.

Kujirai made his professional debut as a voice actor in 2004, landing the lead role of Jenath Dira in the anime television series Get Ride! Amdriver. This marked the beginning of his career in the voice acting industry. Beyond his voice work, he also demonstrated his musical abilities by performing the series second opening theme song, titled READY?.

He is perhaps best known for his association with The Prince of Tennis franchise, where he portrayed the character Kaoru Kaidoh. In 2005, he was cast as Kaidoh in the musical series Tenimyu, becoming the second actor to play the role as a member of the second-generation Seigaku cast. He made his stage debut as the character on January 8, 2005. His portrayal of Kaidoh was not limited to the stage; he reprised the role in the 2006 live-action film adaptation of The Prince of Tennis. Kujirai continued with the musical until March 2006, when he and most of the Seigaku cast graduated from their roles. However, he was brought back to play Kaidoh again for the Advancement Match Rokkaku musical in August 2006, after the actor scheduled to take over the role left the production.

Other notable anime voice roles for Kujirai include Panther (Patrick Spencer) in Eyeshield 21 and Shinichi Uchida in Onegai My Melody. He also had a voice role in the acclaimed animated film The Place Promised in Our Early Days, where he played a male student.

While he has several anime credits, Kujirai is noted for working primarily in live-action stage productions and television dramas. His filmography includes appearances in the television drama Gokusen 3 and its subsequent film, the television film Byakkotai, the live-action adaptation of Yowamushi Pedal as Junta Teshima, and the film Paranormal Activity 2: Tokyo Night. He has also had guest roles in tokusatsu series such as Samurai Sentai Shinkenger and Tomica Hero Rescue Force.

Kujirai is currently employed by the agency Production Ogi.