2064 year. A humanoid object fell from outer space to Earth, which was later called EX-802, but "Angel" for simplicity. In appearance, she looked like a young girl in a futuristic costume. When subject EX-802 woke up, she had no idea where she was. In the course of research, it turned out that the Angel can be used as a combat unit, the strength of which grew when absorbing certain elements. The element types remain unknown. A few years later, scientists noticed an object approaching our planet. Several hundred ships broke into our atmosphere, but were stopped by the military forces of the earth. Angel: It's calling me. Angel: I'm going there immediately! We were powerless to stop her. Angel: Your planet has become my home, even if I am an alien. I will take your side. I will protect people.