La Llorona is a vengeful ghost in Mexican folklore who is said to roam near bodies of water mourning her children whom she drowned in a jealous rage after discovering her husband was unfaithful to her. Whoever hears her crying either suffers misfortune or death and their life becomes unsuccessful in every field.

In mythology and folklore, a vengeful ghost or vengeful spirit is said to be the spirit of a dead person who returns from the afterlife to seek revenge for a cruel, unnatural or unjust death. In certain cultures where funeral and burial or cremation ceremonies are important, such vengeful spirits may also be considered as unhappy ghosts of individuals who have not been given a proper funeral.