Jun Fudo was a teacher who raised her younger brother, Hikaru, while their father was away in the United States. One day, as she and a group of students go on an outdoor trip Jun begins to experience unusual nightmares. Far worse things were about to happen to them, however, when a group of demons, martial artists in human form, in a nearby chalet attempt to rape Jun and the female students in their demon forms. As she was being violated, Jun felt her soul being ripped apart, and, because of this, a terrifying transformation occurs turning her into the Devil Lady. She protects the girls who have survived the demon attacks and kills the demons with her newfound strength. Suddenly, a woman named Lan Asuka appears and says that she was the one who had awakened the sleeping beast within Jun.
Confused by her transformation, Lan Asuka, and her father's sudden appearance and experience, things became too complicated for Jun to understand. Through Professor Fudo's knowledge, he tells a tale of a strange phenomenon that occurred in shantytowns years ago. It was known as the "Devil Beast Syndrome" in which its inhabitants would transform into demons and rape women before eating them with no memories or intelligence of their previous lives and additionally giving them enhanced strength with other abilities.
Professor Fudo does not believe that their "Devil Beast Syndrome" transformation was supernatural, but was actually the next stage of human evolution, calling it "Nature's way of dealing with mankind's overpopulation". He also says that few people were genetically engineered to retain their conscience should the "Devil Beast Syndrome" occur in them, Jun being one of them. With Jun now becoming the Devilman Lady, she will fight for the sake of humanity to protect them from the devil beasts and their creations.
출처: 영어 위키피디아