 In 1986, he made his debut in Yasuhiko's 1986 film "Arion", where he was supervised by Yoshinobu Inano and mentored by lead character designer Sachiko Kamimura, with whom he later collaborated on numerous productions, including being her assistant in "Venus Wars", which was also directed and written by Yasuhiko.Soon after, he began working in numerous other Sunrise series, being the lead character designer in the "Gundam" OVA series "" and "", "" and "Cowboy Bebop".While designing the characters for "Bebop", Kawamoto modeled the character of Ed on composer Yoko Kanno, Spike Spiegel on Arsène Lupin III and "City Hunter", and Ein on a friend's dog, from a suggestion by writer Keiko Nobumoto.