Emi Yusa is the main female protagonist/deuteragonist and the Hero who defeated the Demon King Satan. After forcing the Demon King to retreat from Ente Isla, she followed him to modern day Japan to ensure his destruction. However, just like the Demon Lord, she lost most of her powers upon her arrival and was forced to assume a Japanese name. She was also forced to find employment, and so became a call center agent. She is a half human/half angel.