KURONEKO DANCE

The story follows Soujiro Okita, a nine year old boy. One day, he meets a mysterious man by the river. He soon after meets his friend's new father. However, during a walk, he discovers that his friend's father is the leader of a group and is planning to set fire to the village to create confusion to steal gold. While he was running to the village to warn people, he meets the mysterious man once again. — Description from AniList community (anilist.co).