Formerly employed by Square Enix, he joined them in 1999 as a synthesizer programmer on Legend of Mana, and worked for them on several games.
In addition to his work for Square Enix, he is a composer and guitar player for the bands The Death March and SAWA.
Kato sang some of the songs and wrote the lyrics on Ishimoto's soundtrack for The World Ends with You.
[1] After SAWA disbanded, he formed The Death March in 2012, a band that plays and re-arrange music from soundtracks composed by Ishimoto.
[4] Ishimoto composes songs in many different genres, including rock, hip hop, electronica, and pop.