BackgroundDevilman was born of a merging between the human boy Akira Fudo and the demon general Amon. Akira first became aware of the existence of demons after his best friend from childhood - Ryo Asuka - revealed to him an ancient demon skull discovered by Ryo's father. The normally shy and timid Akira was persuaded by Ryo into entering a modern version of the Black Sabbath in an attempt to draw out a demonic entity and merge with it. Ryo was certain that Akira possessed a pure heart and that such a quality was essential for a human to maintain his own mind when melding with a demon. The Sabbath proved successful, and as it turned out, Akira had melded with one of the most notorious demons of all: Amon, the Beast of Hell. Taking control of Amon's powers, Akira became Devilman and since then has fought against countless demons wreaking havoc upon the Earth.
Unfortunately, Devilman's war against Hell would come to a tragic end. As demon activity increased on Earth, humanity became aware of their presence and mass panic and hysteria led to several violent incidents. In one such occurence, Akira's girlfriend Miki and her entire family were savagely murdered by a gang of psychotic and paranoid demon hunters. Miki's death seemed to break Akira's spirit and he allowed himself to be possessed by Amon, who went on a destructive rampage and attacked humans and demons alike.
Akira would regain control of his body after Amon tracked down Ryo Asuka, who turned out to be Satan. Amon attacked Satan, but Satan called out to Akira, who was trapped in the recesses of Amon's mind. Within his psychic prison, Akira lamented over Miki's death and blamed himself for it. However, Miki's soul seemed to contact him from beyond and she let Akira know that she loved him, even though he had merged with a demon. Thanks to Miki, Akira was able to fight Amon on the psychic plane and managed to defeat him, his pure human heart remaining strong and resilient against the demon. Amon's mind was overwhelmed by Akira's soul and Akira regained control of his body. However, the Earth had already been ravaged by Satan's armies and reduced to a wasteland. Satan revealed himself to be Ryo and claimed that he loved Akira, and had arranged for Akira and Amon to merge so that Akira could survive the world he intended to build. Devilman, of course, rejects Satan's love and the two engage in a final battle to the death. At the conflict's end, Satan reveals to Akira the truth behind their reason for defying God: even though God unintentionally created demons, he wished to destroy them. Satan was appalled at this, believing that even though demons were a violent, bloodthirsty race, they still had a right to live. They joined the demons, then convinced them to enter a state of hibernation in the ice, in order to save strength for the final battle with God. Upon awakening, Satan discovered the beautiful planet they fought for have been ruined by the human race. Enraged at the damage this new race had done, Satan led the demons in a war to exterminate humanity. While they explain this to Akira, Satan realized that in the end, they were no better than God, and begs Akira to forgive them as he dies.
- Superhuman strength - Devilman's strength is superior to all other demons.
- Flight - Devilman flies with a pair of huge bat-like wings on his back.
- Mental control - Being possessed of a human mind, Devilman does not use this ability often. However, when he fought the demon bird Sirene, he used his antennae to grasp Sirene's own antennae and take control of her severed arm.
- Energy projection - Devilman has been shown to fire lasers from his forehead and project some form of heat aura to immolate foes.
- Purity of heart - Possessing a pure heart and noble soul, Akira maintained his own consciousness when he melded with Amon. However, melding with the demon still had an effect on Akira's personality and he became less reserved and more aggressive following the meld.