Satan is an angel who fell from grace when they defied God by siding with the demon race that he planned to destroy, becoming their leader. After an initial victory, Satan and the army of demons go into hibernation to prepare for the final battle. They remain in this state until they wake up two million years later, to discover that the Earth had been taken over by humans. Disgusted by these new creatures, Satan decides to deal with them first before resuming their battle with God.
As part of their plan, demon general Psycho Jenny wipes Satan's memories and replaces them with those of the recently deceased Ryo Asuka in order to infiltrate human society and find their weakness. While living as Ryo, he befriends the timid human boy Akira Fudo, who becomes his best friend, and as Devilman, his greatest foe. Satan wins their war against humanity, but loses everything in the process.
When designing Satan's true form, Go Nagai's intention was for Satan to embody the best of men and women. As such, Satan has a shapely, athletic yet feminine body and breasts, but also a penis and testicles, as they are intersex. They have blond hair and blue eyes, and around thier body are twelve golden (or white) wings.
As Ryo, Satan has a more masculine, though still slender, build. In direct contrast to the always-nude Satan, Ryo dresses rather conservatively, with a preference for long coats, suits, and collared shirts.
Ryo has a very serious, intense, and haunting personality, likely from the threat of the demon apocalypse looming over him. His actions at the Black Sabbath event show that his approach to the war between humans and demons is possibly even more pragmatic than Satan's, instigating violence and dooming an entire group of people to their deaths on the off chance that he or Akira may become devilmen. Despite his initial enthusiasm, the more the war goes on, Ryo becomes convinced that humanity is doomed, even finding dark humor in humanity's futile attempts to delay the inevitable.
Ryo's only known friend is Akira, who he later develops romantic feelings for. Ryo never tells Akira how he feels, but he is very protective of him, and seems to be the only person Ryo expresses any affection toward. Ryo treats Miki Makimura, Akira's friend that is also in love with him, very coldly; getting rid of her is one of Ryo's first goals after awakening his true memories.
Satan has a very strong (albeit misguided) sense of justice, betraying their father God to protect the demon race against God's judgement. This protectiveness does not extend to humanity, which Satan views as a parasite that needs to be eliminated. Ironically, while assuming a human identity, Satan inherits this same sense of justice, but targeted against the demons. Satan only realizes when it's too late to turn back that their treatment of humans is no different than God's treatment of demons.
Powers and Abilities
Satan has a wide range of powers, including flight, telepathy, telekinesis, mind control, and firing massive beams of white light from their hands that can cause much widespread destruction. Satan's telekinetic powers are strong enough to blow bodies apart. They can summon a sword when they battle the forces of God in Devilman Lady; here they also demonstrates the ability to split their consciousness in two. Satan presumably has more powers than other angels due to being 'the child of God'.
Ryo Asuka is a normal human with no supernatural abilities, though he is clearly skilled with guns including a sawed-off shotgun used to scare off crowds, and a sniper rifle for long distance attacks (such as when Sirene attacked Akira). Even while human, Satan's great power sometimes manages to slip through, such as during his encounter with Eader. In this supposedly human form, Ryo recovers from wounds and injuries much faster than a regular human, even the kind that should be fatal. Ryo can also sense demons from their psychic signature, allowing them to track down their locations. He is an adequate fighter, able to get his way through a mob of angry party-goers.
Either form's most dangerous skill however, is thier charisma. The beautiful and attractive appearance alone gives off a sense of leadership and thier personalities comfort many around them. This allows them to have people do whatever they want by manipulating his desires, vices, and passions. This can range from throwing a large party and getting the party-goers to attract and be possessed by demons, or even cause a nationwide panic by revealing to the public about demons while leaving out crucial information about Devilman. Because of this, Satan commands an entire army of demons with absolute loyalty.
Satan, or rather Ryo Asuka, is introduced when he finds Miki and Akira being harassed by a small gang led by Dosu-Roku. Asuka tells Fudo he to come to his home while pulling out a sawed-off shotgun and threatens Dosu-Roku with it and firing to scare the trio away. When Akira asks where he got the gun, Ryo only states that he's facing an enemy. Ryo drives them in his father's car revealing he modified his dad's license. While Akira is confused by Asuka's behavior, Asuka finally tells him that his father Professor Asuka, has died. Asuka informs Akira that his father committed suicide after an event.
They finally arrive at Asuka's home and Asuka tells Akira to be prepared for what he is about to show him. Akira is shown the Demon Mask in Professor Asuka's laboratory. Asuka explains to him that the mask was found by his father during an expedition to Peru. After donning the mask himself, Asuka convinces Akira to wear the mask. He does so, and is instantly greeted by horrific visions of demons in years past. After Akira had recovered from his nightmarish visions, Ryo begins to tell him that he believes the demons still exist, and are hibernating in the coldest parts of the world. He then tells Akira the details about his father's death, including that he had died when failing to fuse with a demon. Because he could not control the demon, his father killed his pets, and then attempted to kill Ryo. However, the little piece of humanity still in his mind regained control of his body and set himself alight to end his plight.
Ryo reveals what little facts he had learned about the demons from reading his fathers notes, and realizes that the demons planned to attack the Earth and retake it for their own very soon. Ryo tells Akira that he needed his help to fight the dawning menace, to which Akira agrees to. They prepare to leave and drive down the road a bit before Ryo picks up a figure in the distance. Once they get closer, the figure reveals herself to be the harpy demoness, Illuge. Illuge summons other demons, forcing Asuka and Akira to fight them off. After the car is destroyed, they walk back to Ryo's house. Ryo begins to tell Akira the real reason he wanted him to come; to fight the demons. But Akira tells him he already knew, and told him he didn't need to apologize. Ryo lights a cigarette laced with drugs, and the two go in through the large steel doors at the end of the corridor.
Inside however, turns out to be a massive rave in full swing. Akira is initially confused, but is then told by Ryo that he was holding a Black Sabbath. Asuka had planned for them to become one with the demons, but they had to attract them first with blood and mayhem. Ryo sets about attacking the guests, before they grab him and start to beat him. Akira tries to intervene but only gets attacked himself. Luckily for them, enough blood is spilled to attract the demons. The demons begin to fuse with the party guests, starting with the demoness, Welvath.
After a period of brief fear without either of them feeling any affects from the demon spirits, Akira successfully dominates the spirit of the mighty demon hero Amon. A brief exchange of dialogue between Akira and the demons transpires, and he then begins to slaughter them. The violence even begins to shock Ryo, amazed as to what his sweet-natured friend was doing; while also questioning if he was still his friend, and not the demon in control. During the fight, Ryo was crushed and pinned down by a demon. Akira, as Devilman, kills the demon before cradling Ryo in his arms, then taking him to a hospital.
The next day, Akira goes to visit his friend in hospital. Ryo asked how Akira was feeling after his transformation. Akira replies just by saying how good he now felt compared to earlier, but was suffering from nightmares. Ryo tells him the nightmares came from the demon he fused with. He then says that the creature who was dominating his nightmares, was a demon even stronger than Amon. The same night, Ryo awakens, having realized something was wrong. He felt that Akira was in danger, so he left the hospital, and grabbed his gun. He came across a man with a motorcycle, which Ryo consequently steals to chase after the action. Meanwhile, Akira, having just defeated Agwel and Ghelmer, is ambushed by the demoness Sirene, who carries him off into the night sky. Ryo climbs to a cliff, and sees Sirene fast approaching. He fires and shoots her several times through the chest, injuring her and causing her to drop Akira. Sirene responds to the attack by firing off one of her claws, knocking Ryo unconscious and pinning him down. A few days later, Akira and Ryo meet in a cafe, and the two talk about humanity's response to the idea of fear, and its irrationality. They eventually decide on the fact that fear largely comes from myths about demons in the days of old, and Akira comes to the decision to destroy all demons.
Late one night, Ryo follows a man named Maegawa home from a restaurant. Waiting till the two of them were in a safe secluded location before he goes up the man and begins the threaten him, attempting to get the man to turn into a demon revealing his true form. The man calls him crazy and insults him, only furthering Ryo's attack as he slashes at his head with a bladed weapon and pierces him through the ear with it. Eventually he begins to transform revealing himself to be the demon Eader, however before Eader can approach and attack he freezes in fear and begins to stutter before Ryo blacks out and falls to the floor. When he awakens it is early morning and engraved on the ground is Eader's shadow. Ryo stumbles along and talks to Akira about what had happened, but Akira only scorns him and says the demon tricked him and got away. Akira then leaves Ryo alone to ponder on the experience.Ryo isn't seen again until the demons devise a mass suicide fusion spree across the world merging with well minded and stable people, causing the two bodies to reject one another and die. Ryo witnesses several of the outbreaks, and it dawns on him that the demons had devised a new strategy and that by merging with random humans it would cause the world to go into mass panic. He runs into Akira and explains to him his theory, to which he agrees. Ryo mentions how he thinks that humanity will begin to turn on each other. Akira doubts this, however on the television they both see a report that the large city of Tsuringrad had been obliterated by a H-Bomb due to the government believing it to have been swamped with non-human entities. Ryo tells Akira that he may now have to combat humanity itself, the very thing he swore to protect as well as the demon menace.
Its not long after the suicide run that the mighty demon lord Zennon announces across the world the existence of the entire demon race and that an attack was imminent. Akira finds Ryo, but he tells Akira not to go out and fight, much to Akira's disbelief. Ryo says to Akira that he needed to stay put as the last hope for humanity. In just under a minute however, Akira witnesses the flames and the carnage around him and attempts to leave. Ryo tries to stop him but Akira hits him and Ryo reluctantly lets him leave to go and fight.
Akira is returned to Ryo after he is knocked out by the demoness Psycho Jenny. Waking up, Akira asks to turn on the TV and sees the carnage that has been caused by the demons with homes in flames across the entirety of Japan and the world. Ryo says that Akira should fight for the honor of humans instead of human lives as he doubted if humanity was going to survive. Akira angered by this throws him against a wall, and tells him that he would not be alone in this fight, believing there to be more Devilmen. Suddenly on the television, a news report about Russia came on, the entire country had been engulfed in a glowing light and at seeing this Ryo flips out and cowers in the corner.
After having recovered from his previous shock, Ryo views the report on Dr. Rainuma's newly formed Demon Busters. This makes him laugh, knowing that it was going to go into a disaster. However, it suddenly hits him how many of the things he had predicted would happen had indeed happened and begins to worry. Confused and wishing to be more of an asset to Akira, Ryo speedily rushes home hoping for some way to possibly become a Devilman or at least find more ways to stop the demons.
When inside he finds the Demon Mask but gets no expected results revealing that the mask was just plasticine and phosphorus paint. Prof. Asuka's notes are also missing. Soon after this he comes across a photo album and looks inside only to find a child named Ryo Asuka who did not look like him and later finds an entry saying Ryo had died in a car crash. Upon this discovery, "Ryo" is suddenly bombarded by demons appearing out of the walls and ceiling before he is approached by one who introduces herself as Psycho Jenny. There she gives Ryo his true memories.
After having disappeared for a short length of time, Akira gives up searching for Ryo decides to go back to the Makimura home. However he finds Ryo being interviewed on television about demons. Akira expects Ryo to dispel all the dangerous misinformation being spread about demons and Devilmen. But shockingly, he betrays Akira by telling the viewing audience a false story of how Akira came to be Devilman that portrays him as a full demon hiding in a human body while showing them a film of his first transformation. Fearing being caught by the Demon Busters, Akira flees from the Makimura household on the family's suggestion after calming down, however unknown to him Akiko and Kozo Makimura are taken in his place.
Hours later during the morning, Akira finds Ryo sitting alone in the wasteland that was once Tokyo. Akira asks if he regretted his actions, to which Ryo says no and goes on to say he has no feelings like that anymore. Akira is enraged by this sudden change, but Ryo only states that Akira should not interfere with his plans. He says that a new age was coming, just like the one before humanity claimed the world for itself. Ryo tells Akira that his merging with Amon was not by chance but happened due to his subconscious will, and that when the end of humanity occurred he didn't want to lose him. After a brief silence Ryo admits that he did not want to fight the Devilman Corps, and offers Akira a unity between the two of them. But Akira stands still and says nothing, having figured out Ryo's true identity as Satan. Ryo then leaves into the sunset. Later on thanks to the actions of Satan, many of Akira's friends and loved ones are killed by mobbing humans including: Tare, Kozo, Akiko, Masa and most importantly Miki. An enraged Akira vows to defeat and Kill Ryo/Satan in a final battle.
The Final Confrontation
Meanwhile, high in the Himalayan Mountains, Zennon congratulates Satan on their plan. Despite this praise, Zennon proceeds to criticize Satan for their one flaw; they had unexpectedly fallen in love with the human, Akira Fudo. He then continues to berate Satan about how they had caused him to lose some of his greatest soldiers. Satan understands this, and reluctantly realizes that Fudo would want to battle with Satan one final time. The Devilman and Demon armies meet to battle over the wasteland that was once China. A battle lasting twenty years breaks out. Much of the landscape is further devastated as the two forces clash. However, in the end Akira loses the fight, and is torn in two.
Satan sits with him on a large, isolated rock in the ocean, as Akira stares up at the moon. Satan tells him about their father God, and how he created the Earth. Afterwards, he planted his seed and left. He then returned a few million years later, and noticed that some creatures had become demons. God considered them to be imperfect, so he attempted to wipe them out entirely. Satan hated their father's actions, and consequently sided with the demons; becoming their leader. They lead a revolt against God, and managed to win and drive his forces back. Satan then voluntarily puts themselves into the ice, and went into hibernation for two billion years. When they awoke, they found the Earth to be very different as to how they remembered. They were angry at the humans for having ruined the Earth of their memories. However, they eventually realized that this made them no better than their father. Satan then begged for forgiveness from Akira, looking over at him. They saw that Akira had closed his eyes, and then comes to the realization that Akira was dead. Satan starts to cry, and the Angels begin to descend down around them.
Devilman: One Summer Day
Set not so long after his fight with Sirene, Akira is seen on the beach with Miki and Ryo. Akira asks Ryo wanted to come in the water with him and Miki, Ryo declined and the two went to play in the water. As Akira and Miki frolic around in the sea, Ryo falls asleep and begins to have strange dreams about Akira. Angrily turning and walking over to Miki. Before leaving Ryo calls out to Akira on the floor. As this was happening Akira and Miki are attacked by the Demon Doelamale and Akira has to transform and kill it to save Miki from its jaws.
Devilman: Fallen Angel
In another short story taking place before the final chapters of the manga, Ryo is seen having a dream seeing flashback to his confrontation with God and then finds himself wandering a frozen cave seeing various monstrosities encased in ice. He comes across himself in his true form as it smashes out of the ice causing to suddenly wake covered in sweat.
The story takes place presumably after the defeat of Sirene in the first manga. It begins as Ryo is awakened by strange tremors under the ground before the caterpillar-like demon Oysnas rips out of the ground and attacks him. However Akira bursts in through the window and promptly kills the demon. Akira gloats to himself about his victory before noticing Ryo in the corner in pain he goes over to notice the walls around him beginning to fade before opening the door to find himself in Vienna, Austria just a year before the outbreak of the first World War. Ryo explains that he thinks they are trapped in a timeslip, Ryo suddenly notices a man walking away from them with a strange demonic scent. They follow him to an art studio where he introduces himself as Harnisch with his assistant Adolf painting in the corner. The two realize that the demon was not there but later notice Adolf and Harnisch walking off towards a large gloomy house. Inside they sell a painting of Adolf's past love Stephanie to the head of the local Jewish bank Schultz. Schultz however had kept Stephanie as a personal slave and when Adolf saw him, Schultz became a demon burning her to death giving the fully named Adolf Hitler an immense hate of the Jewish population. However Akira bursts in and kills Schultz, afterwards the time around him begins to warp again as he and Ryo are spun off to a new time.
As they continue on spinning on through time, Ryo tries to give off some reasons as to why this was happening to them unknown to him that this was in fact happening due to his subconscious powers going on the flux. Afterwards they both hear some disembodied laughter in the distance, they turn to see the brooding Court of Hell standing before them in the far off space. Akira investigates and promptly destroys the demons and the building before they continue on their journey.
Next they find themselves in 200 BC sailing towards the island of Samothrace on several Athenian battle ships. The enemy battleships come out to fight them much to the surprise of Ryo, only to see that the Samothracean soldiers were armed with bazooka's, they then proceed to destroy the Athenian ships. Ryo and Akira are taken prisoner alongside several other soldiers and are brought to the top of the isle where a beautiful angel-like being lands. She is revealed to be the demoness Nike and was handing out modern day weaponry to the Samothracean people. When Akira escapes and chases Nike, Ryo somehow teleports away from the ensuing chaos. He finds Akira and Nike on some rocks, it is revealed the Nike was in fact a past lover of Amon's and that she still had feelings for him. However as the two are about to embrace Ryo pops up behind and decapitates her with a sword, killing her instantly.
Afterwards the two find themselves in France shortly before the French Revolution, Ryo discovers that a demon had taken possession over Marie Antoinette. They locate her and both Akira and Ryo are teleported into her subconscious where they find the demon Poirsenus corrupting her thoughts. Akira transforms and fights the creature, Ryo however tells him to be careful in fighting the creature fearing it may affect her actions, his words go unheard however as Akira rips of the demons head after a short battle.
Ryo and Akira end up in a Native American territory before the Battle of Little Horn. They make friends with some of the locals with Ryo catching the eye of a girl. However upon a small trip from horseback, it was ransacked by settlement soldiers including most of the friends they made. Ryo witnesses Akira wipe them all out in anger.
When Lucifer and his comrades tried to fight back against God's forces they became overwhelmed by God's power. Lucifer was fused together with Yuria and a Pegasus experiment from the flux of energy. Once away from God, Satan spoke with Sirene and a still human Amon. They proposed another attack; using the demons through the same method that empowered them. Amon opposed this, but was forcefully fused with Urga and his dragon Mu.
- Satan/Ryo does not appear in the original anime, with its version of Zennon being the leader of the demons instead. However, the character Iwao Himura bears a resemblance to Ryo, and is sometimes combined with Ryo in adaptations (such as Devilman Grimoire's Asuka Himura). In a later interview, the writers of the anime state that they would have liked to have included them.
- Asuka is meant to be derived from Akshobhya of the Five Dhyani Buddhas, who represents the wisdom of reflection and consciousness. This refers to Asuka's hidden identity as Satan.
- Satan's identity as a fallen angel actually refers to the biblical Fallen Angel, Lucifer. The biblical Satan is actually the name of several figures who would be identified as the Evil Inclination or in older descriptions a servant of God that would test or question the faith of mortals. Lucifer was included as being one of these figures as per his status of treason against God during the transition to Christianity. Satan's design is also reminiscent of Lucifer, as in most renditions of the Bible, the fallen angel was described as being highly charismatic as a result of his rank before he chose to betray God.
- Akuma Kishi goes further in that the male half of Satan's original persona was named Lucifer.
- Satan's appearance post-Devilman Lady is more feminine including a slightly more round face compared to Asuka and had darker eyes.
- In Violence Jack, Satan is once again incarnated as Ryo Asuka but was lovers with Miki Makimura while losing his limbs and becoming the pet of the Slum King. He was also the older brother of Honey with her death being the trigger that regains his memories as Satan.
- In Shin Violence Jack, Jack, who is actually Amon, makes a passing reference to an angel "that sided with demons". A clear allusion to Satan. However, they do not appear in the story.