Grey is Gilliam's bodyguard, a muscular, agile, fast-moving warrior who is handy with knives. Grey was brought onto the train when he was 4 by his parents, who were killed when he was 6. Since then, Gilliam had taken Grey under his wing and Grey became his body guard & a sort of nurse to Gilliam in exchange. Grey had the rare condition of mutism. As he couldn’t speak, he had the artist tattoo words & phrases all over his body to commune with others.