Tanjiro’s earrings are modified hanafuda cards that have been passed down in his family. In Demon Slayer season 1, episode 19, “Hinokami,” Tanjiro’s father Tanjuro wears the earrings. They were also worn by Yoriichi Tsugikuni, the originator of the Breathing Styles. Since he did not have children, it can be assumed that he gave the earrings to Tanjuro, who subsequently handed them down to Tanjiro. The earrings pay homage to Japanese hanafuda playing cards, traditionally floral in design (“hanafuda” means “flower cards”).