Satan was the first Devil as well as the progenitor of the entire Devil race. He is a recurring figure in Vanishing Dragon of Leviathan as well as the great-grandfather of the protagonist, Shirou Fujimura, his third heir who is also the Fourth Progenitor. A fragment of his soul resides in Shirou, granting him incredible potential.
Nothing is known of Satan's appearance other than that he is said to possess a few similarities to Shirou.
When Satan possessed Shirou's body, Shirou's skin turned darker, his hair turned black, his eyes turned blood-red, and his body produced a long, demon-like tail as well as eight Devil wings despite Shirou's body limiting his power.
Despite his brief appearance possessing Shirou's body, Satan has shown himself to possess quite a few similarities in personality with Shirou such as their charisma and their care for their comrades. Satan is also somewhat chivalrous and a gentleman, looking down on those who raise a hand to a woman.
However, he possesses an immature and forgetful side such as not remembering Kokabiel's name (whether this is deliberate or if he was making fun of Kokabiel is unknown at the time) and even failing to acknowledge that he (in Shirou's body) was missing an arm from earlier. Satan even made outright comparisons between his regenerative abilities and Dragon Ball Z.
He also possesses the same violent tendencies as Shirou, proving more sadistic as when he severed Kokabiel's arm before killing him. He also tended to show-off his abilities to observers and used complete overkill methods to slay Kokabiel.
Underneath all of this, Satan is very empathetic and caring, showing regret for not saving Shirou's soul from being damaged and making Shirou's friends cry. He also feels responsible enough over Shirou that he initially refuses to release a possibly amnesiac Shirou to return to his body because he believed that Shirou's friends might force him to try to become who he was at the cost of Shirou's own happiness and becoming pleased when they spoke their desire to let Shirou live as he wishes regardless of who he ends up becoming.
He was also willing to warn Shirou of who his true enemy might be.
Not much is known about Satan's past other than that he is the Original Devil as well as the creator and father of the Devil race, ruling over them along with his six other most powerful creations, the other members of the Original Maous. He led the Devils in the war between the Devils, Angels, and Fallen Angels, perishing sometime near the end of the war along with God from the Bible.
Satan makes his first actual appearance in Volume 3, possessing Shirou after he is nearly killed by Kokabiel. With his incredible power, Satan makes quick work of Kokabiel, killing him. After hearing the heartfelt words of Shirou's comrades, he returns to the depths of Shirou's soul, allowing Shirou to take control of his body once again, leaving Shirou with ominous words: "The true enemy is the one closest to you."
Powers & Abilities Edit
Immense Demonic Power: Being the progenitor of the Devils and their first leader, Satan could be referred to as "the Strongest Devil" prior to the birth of the three Super Devils. While their power surpasses those of the other Maous, it is unknown who would be the victor in a battle between Satan and one of the three. The only thing known is that such a battle would level the world a hundred times over due to the clash of demonic power.
The King's Power: Being the creator of the Devils from which their traits were born, Satan possessed the ability to wield all of the powers that once belonging to him, the powers that were passed down to the 72 Pillars. He is also able to use the demonic [Satan Flames] from which all of these abilities were born. While the flames are powerful, they are but a base form.
Master Hand-to-Hand Combatant: Due to his raw physical strength, there were few who could fight hand-to-hand with Satan and those who could would find themselves matched by one who has trained their body to the fullest, being nearly impossible to overwhelm in physical confrontation.
Flight: Being a Devil, Satan can fly using his wings.