 In 1994, T.utu put out their first album, and Utsunomiya, as one of the members of the former members of T.utu, split off into another band named Boyo-Bozo which Ishii also helped compose music for.After Boyo-Bozo broke up, Ishii composed music for a number of other artists including Lazy Knack, Tomoe Shinohara, Masayuki Suzuki, and V6.He also helped produce Naoto Kine's album "Liquid Sun", Crystal Kay's first album "C.L.L～Crystal Lover Light", and Daisuke Asakura's "Siren's Melody" single.