Michael Gedōin

"Welcome, unsightly cockroaches. I am the head of this Illuminati eastern research facility...Michael Gedōin. How dare you invade my sanctuary. This is the sanctuary of the experiments on the Elixir of Immortality! Those who invade the sanctuary deserve only death! I will make you fully understand the extent of your sin. I will exterminate every last one of you!"

- Michael Gedōin to intruders. "I don't. I haaaate humans! Surely you know that you use various animals in your scientific experiments. You slaughter other beings in order to live. That's the kind of living creatures humans are! Shouldn't you use your own selves in the first place? Humans using humans in experiments, this is only fair!"

- Michael expressing both his hatred and trying to justify his crimes.

Michael Gedōin is a villain found only in the manga Blue Exorcist and a scientist who is obsessed with gaining his bosses: Lucifer (the oldest son of Satan), praise and unlocking the secrets to immortality.

Personality
Michael's personality is that of a rude, manipulative, sadistic and cruel scientist who doesn't care who he has to hurt as long as he obtains what he wants in the end. He is shown to mock his test subjects on how helpless they are in their current state. Michael is also shown to be somewhat perverted as he tells a young teenager that she has "developed nicely" all while telling her provided that her physical is acceptable he will conduct cruel experiments on her. When confronted with others mentioning how depraved he is, Michael merely claims to hate humanity and that humanity is itself evil and cruel all while pointing out he has no remorse for his actions. It is shown that even his fellow Illuminate members do not agree with him or his actions as even Lucifer expresses nothing but disgust for his cruelty. Michael can be considered a coward as he purposely avoided any form of physical combat or anything unless he felt like he was in control such as those he tricked into being test subjects and when he became a powerful Demon when he felt like it was his only chance to win.

Appearance
Michael is portrayed as a rather short, overweight man with thick eyelashes, rather wide eyes accompanied by large lips and teeth. His attire consists of the seemingly dark yet standard Illuminati uniform, a pair of very tiny reading glasses that he wears constantly and a lab coat over said uniform. A noticeable feature is that Michael is nearly always shown to be smiling especially when others are in terrible pain.

History
Michael is first shown to be laughing as he Izumo Kamiki with her mother whom he has experimented on for years claiming her mother was no longer of any use to him and provided Izumo was physically healthy enough he'd use her as his next test subject. When Izumo nervously points out she is yet to be an official Exorcist like he said he needed her to be only for Michael to joyfully point out due to his "genius" he's found an alternative route and that is no longer necessary. He then makes a quick suggestive comment that she has "developed nicely" and that soon he would gladly do experiments on her and enjoy her suffering. Not much later it is revealed through flashback that a former college by the name of Maria Yoshida had tried to save Izumo after saving her younger sister, Tsukumo Kamiki, by sending Tsukumo to be adopted. Maria tells Izumo to stay in her room while she gets some data only for Michael to show up and cornering Maria while revealing that they also have Izumo who had disobeyed Maria's order. Michael threatens to inject Maria with the newest prototype of the Elixir of Immortality but offers her a chance to be spared if she recites the Illuminati creed. Despite Maria doing so Michael still injects her claiming he would never forgive a traitor or show mercy. As expected the prototype kills Maria in a painful fashion by shutting down her nervous system all while Michael watches in sadistic pleasure.

It is revealed Michael's research had turned his victims into zombies which he see's as his own personal army. When Rin and the other infiltrate the Illuminati base and discover said monsters Michael unleashes the a large amount while demanding to have the security cameras zoom in so he can enjoy the carnage. However once he sees that Rin and Yukio are the sons of Satan he decides to capture them as a gift for Lucifer. Upon hearing that Izumo was captured and the others fell into his trap Michael is delighted especially when he hears Lucifer is awake. However one of his fellow colleges mention that he shouldn't be so prone to merely call Lucifer by his full name and that he should get everything straightened out to where when he explains it everything will make sense. While his college leaves he outwardly says that he will only to be mentally mocking her by calling her a pig and that he'd show her. Soon after Michael is shown to Lucifer who he praises who then states he's grateful for the current Elixir and then remembers this is the first time they meet in person. As Michael brags of capturing Rin and how they should kill him, Lucifer disagrees and says he will send him back to Samuel (Mephisto Pheles) at some point much to Michael's discomfort. Michael then mentally curses his female college until Lucifer's body is starting to get over worked. As Lucifer points out success depends on Michael's Elixir and he asks him to create a perfect body for his Father to which Michael quickly agrees.

Even upon hearing Izumo has less than a one percent chance of survival from a transfer of a powerful Demon that was necessary for the experiment, Michael planned to have it go on as originally planned. Realizing if he failed it would likely end his career Michael decides to kill Rin despite his orders to spare him and make it look like it was necessary so he would still be valued by Lucifer. Even upon being reminded of this by Renzo, Michael fantasizes on how he will be able to pull it off and that Lucifer would embrace him. Upon being asked by Renzo if he needs to get Michael's female college Michael merely responds that he has his own military power. It is then revealed Michael had unleashed giant monstrous zombies to kill Rin as his friends while he watched from his safe distance. As the heroes fight and escape the monsters Michael begins to panic but quickly tries to calm back down. However as he is again reminded of the low probability of success and how he should report to Lucifer about the situation he merely yells at Renzo to shut up. Michael then introduces himself and threatens to kill everyone present all while admitting he drugs to local food so he can trap the tourist that get addicted just so he can have as many test subjects as he wants.

As the others call him a monster for his actions he points out not only that he hates humanity but thinks they are evil by nature. As the heroes fight a monstrous zombie and to free Izumo, Michael gets Izumo's transfer prepared so he can create the ideal Elixir for his master and himself. It turns out Michael created a "Savior mask" that would force a Demon to possess a body and stay in it regardless of the compatibility and he planned to use it on Izumo for his goals. As he reveals the process will most likely kill her he tells her to give in all while watching her suffering with pleasure. Just as it looks like Izumo is doomed Rin jumps in and starts to ruin Michael's plans. As he insults them Rin knocks Michael back in anger of the pain he has caused to others for so long. In fear Michael demands backup and unleashes a horde of zombies. As he is observing the battle Izumo's mother is able to reabsorb the Demon and when she dies from her body finally giving out Michael is left confused and upset over his failure.

Desperate for victory and revenge Michael decides to put on the Savior mask and admits that he had taken the Elixir in the past and gave up on his dream of becoming Demonic or being possessed but now he would do so to avenge his failure. Upon his transformation into a hideous Demon he precedes to attack Rin and the others all while seemingly remaining in full control of said form unlike Izumo who lost control of her body when possessed possibly referring to his evil nature being stronger than the Demon who seemingly was only used to gain power. After a intense battle Michael is beaten though alive due to the Elixir. Eventually he awakens only to realize he is no longer in the base he used to run. Confused Michael is informed on how the True Cross Order had come and how the base was always prepared for this. However as Lucifer points out how he was there not only to make sure his body could recover but to see if their was a traitor was among his group admitting he didn't wish to suspect Michael but no knows of his shady actions. Michael pleads he only wanted to make Lucifer happy and says now that he has "transcended" humanity he can do even better. However Lucifer says Michael's like many humans in the fact he's selfish, and cruel but to an even higher degree with delusions of grandeur before he killing him by burning until nothing remains to ensure he can never return.