Arai made his screen debut in
Isao Yukisada's
Go in 2001 when he was 22 years old. His next film role was the emotionally disturbed senior high school student Aoki in
Toshiaki Toyoda's
Blue Spring, which won him the Best New Actor award at the 17th Takasaki Film Festival. In 2011, Arai co-starred as Detective Kazuhiko Soga in a one-off TV crime thriller
Douki with co-stars
Ryuhei Matsuda as Detective Ryota Udagawa and
Chiaki Kuriyama as Michiru Soga. The June 2012 issue of
Switch, a Japanese arts and media magazine, features a special segment on top ten manga that teaches love and passion, chosen by Japanese actors, artists and musicians including Arai, who chose
Bakuman while explaining: "You should up your girl power by learning how to behave like a heroine." Arai was represented by Anore Inc., a talent agency founded in 1996 by actor
Tadanobu Asano, Asano's father Yukihisa Sato and Asano's musician brother Kujun Sato. The talent agency terminated his contract shortly after Arai's arrest on February 1, 2019. ==Personal life==