Satou is an Ajin. He is referred to by officials such as Yuu Tosaki as Hat (帽子, Boshi). His real name is Samuel T. Owen.

While Satou's father is British and his mother is Chinese, he himself is from the United States of America. He was part of the United States Marine Corps in the past. Before dying for the first time he had a large x-shaped scar on the left side of his face and was missing his right leg.

He is passionate about video games and gaming in general.