Jyoubu, the infant baby brother in Hiwou's family, flees their destroyed village with siblings Hiwou, Sai, Mayu, and Tetsu, alongside friends Shishi and Machi. Throughout their journey across Japan, he fulfills a functional role in operating the giant clockwork doll Homura. During activation sequences requiring multiple operators, Jyoubu serves as a living counterweight: positioned inside a suspended bowl-like apparatus, his swinging motions mechanically contribute to initiating Homura's transformation or movement processes.