Kimotsuki is perhaps best known for voicing the characters of Takeshi Gouda in the original 1973 Doraemon television anime and Suneo in the 1979 anime. He voiced Gouda initially before Kazuya Tatekabe took over the role in 1979, whereupon Kimotsuki took over Shun Yashiro‘s role as Suneo. He has also voiced roles in such anime as Soreike! Anpanman (Horrorman), Galaxy Express 999 (Conductor), the 1979 Cyborg 009 anime (Great Briten/007), Magical Angel Creamy Mami (Nega), Kaibutsu-kun (Dracula), Osomatsu-kun(Iyami), and Yuki Yuna Is a Hero (Yoshiteru).
He also performed in Japanese dubs for American animated films such as The Aristocats and The Little Mermaid. He also voiced Tom in the Japanese dub of Tom & Jerry. Additionaly, he voiced Jiminy Cricket in the Japanese dub of Disney’s Pinnochio, a role that he revisited in Square Enix‘s Kingdom Hearts video game series.