In 2003, Kato started her career as a singer when she provided vocal to Reggae Disco Rockers' song "Cherry Oh!

Kato's second studio album Diamond Princess achieved minor commercial success, certified gold by the RIAJ and peaking at number five in Japan.

Her fifth studio album Heaven (2010) debuted atop on the Oricon chart and has yielded two platinum singles, "Why" and "Last Love".

The former has yielded three gold-certified songs, "Yūsha Tach", "Lovers Part II", and "Konya wa Boogie Back".

Her tenth studio album, Femme Fatale (2018) was released to a minor commercial success, only reaching number eight in Japan.

Kato is known for popularizing sampling in the J-pop scene, and has incorporated a wide range of tracks in her songs.

Regarded as one of the biggest J-pop musicians in the late 2000s and the early 2010s, Kato has sold over 12.6 million records and ringtones.