Number Girl
Shutoku's vocal style is one of the band's most distinctive traits, a combination of shaky singing, aggressive growls and screams, spoken word, and occasional rapping. Although most lyrics are in Japanese, his strong songwriting was one of the band's most critically lauded aspects. Shutoku's early lyrics dealt with conventional themes such as high school and girls, reflecting adolescent aggression rather typical of nineties hard rock; however, with later albums, Mukai would begin exploring deeper lyrical themes, such as disillusionment with Japanese culture and harsh social criticism, that distinguished Number Girl from their peers.