Sui generis
Sui generis (; ) is a Latin phrase that means "of its (his, her, their) own kind; in a class by itself; unique."
List of supernatural beings in Chinese folklore
"Shui gui" () are the spirits of people who drowned. They lurk in the place where they died, drag unsuspecting victims underwater, and drown them to take possession of their bodies. This process is known as "ti shen" (), in which the spirit returns to life in the victim's body while the victim's spirit takes the "shui gui"'s place and constantly seeks to take control of another living person's body.