delicochan:

Ajin: Demi-Human 
They’re immortal, which means they won’t die no matter what. They first appeared 17 years ago in Africa. The same year you guys were born. There, they were soldiers who were given the name “Divine Warriors”. Since one can’t know if a person is an Ajin unless they don’t die when they should, there is a possibility that there is even some among us.