After she was spotted and recruited with 1998's television commercial appearance by a current entertainment production, she made her debut in 1999. In 2002, Kat appeared alongside Masanobu Ando in the film TOKYO 10+01, which was heavily influenced by Battle Royale, in which Ando had portrayed the character Kazuo Kiriyama. Coincidentally a year later, she appeared in the sequel, Battle Royale II: Requiem, as a member of the terrorist group Wild Seven. She also portrayed the Kamen Rider franchise first official female Rider, Kamen Rider Femme.