Mewra left his home with his father's rifle, determined to join the armed forces to protect his home. Much later, soldier Mewra finds himself stranded on a battlefield filled with deadly mecha. He happens upon a mysterious young woman, named Tyche, with red eyes. He quickly decides to help this seemingly lost and helpless girl. However, she is much more important to the war than he could have imagined, and his determination to protect her is going to change his life!