An epidemic of smallpox once broke out in the region. People prayed to the gods for help.
In the Utsunomiya town of Tochigi, a farmer caught a big yellow carp called funa (鮒) or kifuna in the river Tagawa, and fed it to his sick family members stricken with smallpox. As the sick patients soon recovered, kibuna has since been loved by people of Utsunomiya as a charm for good health. (According to some versions, many people ate the carp and were healed)
The yellow carp has since been regarded as a messenger of the deity of the Futaarayama jinja 二荒山神社 and the Kibuna papier-mache amulet is a folk craft of Utsunomiya town.
Yellow carp (ki-buna) amulets are sold at the shrine during the New Year season to ward off bad luck and illness in the coming year. The yellow carpfish is now a symbol of Utsunomiya town.
Sources and references:
Dr Gabi Greve’s Daruma Museum “Omamori – Japanese Amulets”