Her songs appeared in various anime including Paradise Kiss, Mobile Suit Gundam 00, Soul Eater, Pokémon, Gin Tama, and Bakuman.
She modeled for Italian fashion house Fiorucci, and hosted the MTV Japan show Breakdown.
In 1995, after bassist Shunsaku Okuda and guitarist Ryo Matsui heard her sing in an amateur talent contest, Kawase was asked to join The Brilliant Green as the lead vocalist.
After scoring another number one hit with "Tsumetai Hana", they released their self-titled debut album which sold over one million copies in just two days.
On the back of this success their first national tour, titled "There Will Be Live There," sold out across Japan in only three minutes.
[2] In 2013, Kawase started releasing music from all her personas in commemoration of the Brilliant Green's 15th anniversary.
In 2001, Kawase joined DefStar Records and launched her solo career under the character of Tommy february6 (named from a combination of her nickname and birth date) with "Everyday at the Bus Stop".
It is presented in a mock travel guide format, including features such as restaurant reviews, sightseeing hotspots and cultural information.
In keeping with the character's outwardly cute personality, crude outline sketches of animals and fairies litter the pages (as seen on the cover) alongside thought bubbles gracing many of the pictures, which have the distinct appearance of doodles.
At this point, the original concept started to disappoint her and Kawase began to feel that the character could no longer maintain its purity.
She finished this productive phase with the Heavy Starry Tour: four live performances as Tommy heavenly6 during March 2007.
In April 2009, Tommy heavenly6 released a new concept album, titled I Kill My Heart, which was composed mostly by Chiffon Brownie.
Finally in December 2010, Kawase announced via her Twitter page the possibility for a third studio album under the Tommy february6 persona.
On November 22, 2003 Kawase announced her marriage to The Brilliant Green's fellow member and bassist, Shunsaku Okuda.
It is presented in a mock travel guide format, including features such as restaurant reviews, sightseeing hotspots and cultural information.
In keeping with the character's outwardly cute personality, crude outline sketches of animals and fairies litter the pages (as seen on the cover) alongside thought bubbles gracing many of the pictures, which have the distinct appearance of doodles.
Kawase has also made an appearance as the voice of Pikki in the anime series Piroppo, briefly modelled for Italian fashion house Fiorucci and for a period of time hosted Break Down, an MTV show.