Trapped in his tomb, but alive, the God of Pain awaits his uleashing, said to be at the end of the world, he uses his only powers he can and calls to him 2 people, a man and a women to reliquish him from his prison. The man and the women, decieved by them thinking it a person trapped, go after to help the God of Pain unwittily and let him destroy the world
The size and number of knots in hair, tied around neck, or hanging from belt could signify family, importance, worship, guild affiliations. Being able to translate the meaning of the size and placement of knots can give you a a large understanding of who somebody is.
May be used in a more barbaric society. Where in cities peoples clothes and crests show who they are, barbarians have no need for this so use knots.