The legendary rulers of the Mibu Clan and their most powerful agents.
The progenitor of the Mibu Clan and its first ruler.
The First Crimson King is encountered by Kyo, as he is in fact Kyo's ancestor and the soul of Tenro, Kyo's BFS. The Shodai Aka no Ou merely wanted his people to live lives of comfort and happiness, but ultimately realized that their godlike power only served to lead to their self-destruction, as the fulfillment of all their desires left them with only one source of true stimulation... slaughter through battle, most especially of each other. He grants Kyo the mark of the True Crimson King after Kyo overcomes his demon blood (the very thing that brought about the downfall of the rest of the True Mibu).
- The Atoner: He regrets his failure to save the True Mibu from their demonic nature, and guides Kyo in an attempt to fix his mistakes.
- Dark Is Not Evil: He looks intimidating and has a darker color scheme, but he's the closest thing this manga has to a Big Good.
- Expy: He bears some notable similarities to Raizen, being an ancient ancestor of the protagonist who at one point tries to take over the body of said protagonist to fight someone out of his league.
- Friend to All Children: He appears to Kyo surrounded by cute Mibu tykes whom he happily allows to climb all over him. He also explains that the reason the Mibu became gods in the first place was because he wanted his children to lead happy and untroubled lives.
- Horned Humanoid: The horns are actually fake and removable.
- It Amused Me: The reason he even bothered with the above-mentioned horns and "Demon Lord" getup. He takes great pleasure in messing with Kyo.
- Luke, I Am Your Father: He's heavily implied to be one of Kyo's ancestors, but probably not his actual father.
- Precursors: He's the first Crimson King.
- Reasonable Authority Figure: He and Kyosaburo (the "current" Crimson King before the Former had him killed) are the only Mibu rulers shown who weren't megalomaniacal tyrants.
- Sealed Good in a Can: His spirit is bound to Tenro and lives within the blade.
- Wacky Parent, Serious Child: He's probably not actually Kyo's father, but he is the only relative we ever meet. He's also ridiculous, wearing fake horns and pretending to be a scary demon lord as a joke. Before he releases Kyo from his pocket dimension inside Tenro, he even sticks the fake horns on Kyo's head.
A mysterious figure in the story. His identity, nature and intentions are a mystery throughout much of the story. When the Former Crimson King first appears, he seems to have strangely benevolent inclinations towards Kyo. There are also mysterious hints that he seems to be setting up a competition between Kyo and Kyoshiro to see who will be the legitimate successor to his title.
The Former Crimson King is initially presented as one of the last of the True Mibu (Kyo being the other). Kyoshiro and the other Red Cross Knights were created from his flesh and blood to serve as his own corps of secret assassins. However, all of this masks a still greater secret. The Former Crimson King is actually Mibu Kyoichiro, the first of the Red Cross Knights, and is himself a construct created by the True Mibu. When the True Mibu wiped themselves out, the Former Crimson King hid his status as one of their battle puppets and ruled over the Mibu in their stead. Over millennia, he has become overwhelmed by the depravity and violence he witnesses in the human world, and has come to the ultimate conclusion that everything must be destroyed in order for there to be true peace.
- Adapted Out: In the anime, the Mibu have no King, crimson or not. The same goes for all of the Red Cross Knights.
- Affably Evil: He sounds perfectly reasonable and is surprisingly friendly toward the protagonists. At first.
- Faux Affably Evil: Once pushed, he snaps and becomes far from affable.
- A God Am I: Played terrifyingly straight. He even has the power to create and destroy at will. Subverted at the end when it is revealed that he too is one of the True Mibu's battle dolls, attempting to rule in their stead to maintain their legacy. He was the closest they ever got to replicating themselves, so his power rivals theirs.
- All Your Powers Combined: He can use every technique ever developed by the Mibu. Including the Mumyo Jinpu Ryuu.
- Authority Equals Asskicking: He leads the Mibu and is far and away the most powerful of them.
- Badass Bookworm: Initially, he pretends that he is badly nearsighted thanks to countless years of studying books and scrolls. Often quoted Confucius early on in the story.
- Beat Still, My Heart: That sealed room that had to be unlocked with the four Muramasa swords, the one hiding the secret that cost Kyosaburo, Nozomu and Ian their lives? It contains his still-beating heart, removed from his body years ago. It has the Crimson Cross carved into it, which reveals that he is the first Knight, Mibu Kyoichiro — not one of the True Mibu as he claims.
- Big Bad: Of the series.
- Biseinen: When he stops playing goofy.
- Blind Without 'Em: In his first non-silhouetted appearance, he talks to pillars and walks into walls, even with his glasses on! However, once he starts getting serious, this goes out the window.
- Cloudcuckoolander: He runs into walls and goes into a daze, but this spacey quirk just makes him appear more disturbing because of his apparent detachment from reality.
- Disney Villain Death: Subverted. He's already dying when the Crimson Tower crumbles with him inside. The fall doesn't kill him, but his body disintegrates when he hits the ground in Shihodo's graveyard.
- Establishing Character Moment: He gets two.
- One of his first scenes is when he shows up in the dungeon where Hishigi has imprisoned Shinrei. At first he's just acting silly and weird, and Shinrei has no idea who he is. And then the mysterious stranger walks away, and the impenetrable cell crumbles. This establishes that he's much more powerful than his odd behavior implies.
- His next scene establishes his viciousness. He starts off spacey and talks to pillars thinking they're Fubuki. Tokito thinks he's ridiculous, believing that Fubuki is leading the Mibu already and the king is just a figurehead. But when the king senses Tokito's thoughts of attacking him, his Killing Intent shows Tokito his own death and reduces him to cowering on the floor, shaking in terror.
- Evil Redhead
- Killing Intent: It's so intense that he can make people see their own deaths and paralyze them with fear.
- Lack of Empathy: His response to Muramasa's plea to help the Mibu Clan is to say he can just make more after they die off, so they can feel free to do so.
- Light Is Not Good: Dresses in white and acts like a saint at first, but he is not a good person.
- Dark Is Evil: He has a darker outfit in his final battle with Kyo.
- Might Makes Right
- My God, What Have I Done?: After The Reveal that he is Mibu Kyoichiro, he realizes that he has lost himself in the hatred and destruction in which he has lived for ages. He recalls his heart into his broken body, causing the Crimson Tower to crumble as he dies.
- Not So Omniscient After All: Near the end, he kidnaps Yuuya and believes that she's a seer of great power like Nozomu and Sakuya, even though she denies and there was no implication of such a thing in the first place.
- Obfuscating Stupidity: In his first real appearance outside of silhouette, he appears to be incredibly near-sighted, talking to pillars and walking into walls. But when Tokito steps out of line....
- Omnicidal Maniac: Comes to the conclusion that mankind is beyond redemption and decides they must all be wiped out.
- Stepford Smiler: When he first appears, the Crimson King's appearance is positively goofy. At times he makes it incredibly intimidating. Later, we discover that his smile hides the pain and madness that have resulted from watching the senseless violence in human society for millennia.
- Synchronization: He does this to Sakuya and Yuya's hearts to deliver one hell of a Sadistic Choice.
- Villainous Breakdown: Has one when Benitora and Sasuke show everyone his heart, revealing the truth. He screams that he has surpassed the True Mibu, and that they were monsters who deserved to die out.
- Well-Intentioned Extremist: He wants to save the Mibu clan, but time jaded him into becoming a tyrant who believes in Might Makes Right.
- Xanatos Gambit: He thinks he has one set up when he pits Kyo and Kyoshiro against each other. At this point, Kyoshiro is in Kyo's body and vice versa. No matter which one kills the other, there will be no True Mibu left, because Kyo is the last and either his soul or his body will be destroyed. They escape it when Kyoshiro reveals that his defection to the King's side was false, and he has always planned to give Kyo's body back to him.
He was intended to be the Current Crimson King, but was deposed and imprisoned by the previous one for developing the Mumyou-Jinpuu-Ryu (a school designed to be capable of killing God — AKA the Former Crimson King) and teaching it to the renegade, Muramasa. He befriended a young Kyoshiro and introduced him to Sakuya. Many years later, when Kyoshiro had fallen under the thrall of the Former Crimson King, he no longer resembled the kind boy that he once was. Kyosaburo made a last ditch attempt to find the ultimate secret that lay behind the doors in the palace, only to be stopped and killed by Kyoshiro acting on the Former's orders. His death ultimately broke Kyoshiro free from the King's power and prompted Kyoshiro and Sakuya to leave the Mibu. Kyosaburo was the third of the Crimson Cross Knights.
- See Chinmei
- See Mibu Kyoshiro