|Nome japonês||草場 一平（くさば いっぺい）|
|Estréia no Mangá||Chapter 13|
|Estréia no Anime||Episode 1|
|Galeria de Imagens|
Ippei Kusaba (草場 一平, Kusaba Ippei) was a Rank 3 Bureau Investigator working at CCG's branch in the 20th ward and the partner of Yasunori Nakajima.
Ippei was a young man with short brown hair and round glasses, just like the other investigators, he wore a formal suit with blue tie.
Together with his partner Nakajima, Kusaba took part in the investigation of Ryouko Fueguchi alias Suspect 723 that was led by Kureo Mado and Koutarou Amon. As part of this investigation, he observed Ryouko Fueguchi and witnessed that she was visiting a grave.