Iku is recognized as one of the original creators of the anime television series Bubu Chacha, which first premiered in Japan in 1999. The series, produced by the animation studios Daume and Japan Digital Entertainment, was a collaborative creation; alongside Iku, the other credited original creators were the director Tetsurō Amino, writer Akira Okeya, and Takeshi Anzai. Iku is credited in this capacity for both the initial 1999 series, Bubu Chacha, and its sequel, Daisuki! Bubu Chacha (titled I Love Bubu Chacha! in English), which aired in 2001.

The series Bubu Chacha is a slice of life comedy that follows a young boy named Randy and his pet dog, Chacha, who is reincarnated as a toy car after dying in an accident while saving the boy’s life. Iku’s role as an original creator is foundational to the series' concept and development. The anime was broadcast on the Japanese network NHK and has been distributed internationally, receiving various localized titles such as I Love Bubu Chacha!.