Emi Yusa

Emi Yusa  is 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.

Emilia Justina was born to an ordinary farmer named Nord Justina, and the archangel Lailah. Knowing she had committed a taboo by birthing a child to a human, her mother fled, leaving Emilia to be raised by her father on his farm located somewhere on the Western Continent. During Satan's conquest, the child lived a peaceful life with her father. One day the Ente Islan Church arrived at her home to train Emilia as the Hero who could free the world of the Demon King Satan. The clergy went on to explain her responsibilities as the daughter of an angel. Her father confirmed this by telling Emilia of her mother's true nature, allowing her to be passed into the care of the Church. Her motivation was fueled when she received news of her father's apparent death when the Demon King's army laid waste to their fields. In reality, Nord Justina was taken by Lailah and hidden safely on Earth.

She fought alongside the Allied Knights Order to drive back the evil horde. Emilia defeated Lucifer in the West, freeing her home continent from the demon oppression. Satan declared he would leave Ente Isla in the hands of the humans, vowing one day to return and conquer it for himself. Opening a vortex in the sky, he fled to another world along with Alciel. Emilia pursued him through the portal in order to finish their battle.

Upon reaching the other side of the Gate, the Hero found herself alone on Earth and bereft of the majority of her powers. She forged an identity under the alias "Emi Yusa" while registering herself as an adult in her twenties. Desiring to find and finish the Demon King, Emi continued her search and moved into a small apartment somewhere in Tokyo, getting a job at a call center to sustain her living expenses. During this time she established a friendly relationship with her co-worker Rika Suzuki.