They’ve had many titles and roles through all of history, in every culture and time: those who are there when we die, to escort our soul to whatever comes next.
The modern term is Psychopomp, but that’s always up to change.
What they really are is helpers. They help His father, Cronus ate him, for reasons unknown; his sister ... More – Death – giving him aid by escorting souls who are in fair shape at death to the gateway of the next life. Souls that are damaged need Hades’s personal touch, which is a whole other issue, but for the most part, Psychopomps have a deeply important and difficult job.
His father, Cronus ate him, for reasons unknown; his sister ... More only picks people with a keen understanding of mind and emotion, with the compassion to be gentle to those who have died, yet with the strength of character to resolve any attempted postmortem shenanigans. It’s a crucial role; all are grateful for the chance to help others in death as they often have in life.