As a teen Nathaniel made the selfish act of committing suicide and as soon as he noticed his mistake pleaded to the death for another chance. The death agreed, and told him he can keep living with two conditions the first one was his silent and the second one was helping him with one of his chores, this chore consist on guiding the deceased through a long way until reaching a terminal, at that point he will have to call a train and give the person a token so the person can get on board and be taken to his "resting place".
"Six souls for each day you live and in your last day of work you will find only one token hanging from your uniform with your name engraved on it"