Shiba was born on February 15, 1971, in Kanagawa Prefecture, Japan. She was a fan of video games and aimed to work in the industry but turned to animation, joining J.C.Staff after graduating from Gakkou Houjin Chiyoda Gakuen's animation department. Shiba joined Studio C-Zoo alongside Yukiko Ban and Tatsuya Oka in 2009.
Her credits in the anime industry include character design on .hack//Sign and Kuroshitsuji, and animation direction on the Yowamushi Pedal series and D.Gray-man. She was an animation director and designed characters for Noir, Tsubasa Chronicle and its second season, and Kuroshitsuji II.