The hanafuda earrings that Tanjiro Kamado wears in the anime "Demon Slayer" hold sentimental value and significance. They originally belonged to his father, who wore them as a reminder of his family and their bond. Tanjiro wears them as a symbol of his determination to protect his loved ones and carry on his father's legacy. Additionally, the hanafuda earrings represent the Kamado family's connection to nature and the changing seasons, as hanafuda cards are often associated with traditional Japanese culture and symbolism.