In Japanese folklore, hitodama are balls of fire that mainly float in the middle of the night. They are said to be "souls of the dead that have separated from their bodies", which is where their name comes from.

Onibi is a type of atmospheric ghost light in legends of Japan. According to folklore, they are the spirits born from the corpses of humans and animals. They are also said to be resentful people that have become fire and appeared. Also, sometimes the words "will-o'-wisp" or "jack-o'-lantern" are translated into Japanese as "onibi".