Nichinaga Oumi

"All is for the sake of revenge."

- Nichinaga's words to his soldiers

Nichinaga Oumi (逢海日永, Oumi Nichinaga), more commonly referred to as The Commander (総帥, Sousui), is the co-founder and supreme commander of The Shadow Organization. For various reasons, including seeking vengeance against his adopted brother Tsukihisa after numerous betrayals, he is completely obsessed with destroying his brother, their organization, and everyone around him after that, including his own followers.

Appearance
Nichinaga has had three confirmed identities in the series: the young man in which he first met Suigetsu ; The King, an elderly man with long, white hair ; and En (遠), a young, dark-haired boy. Whatever body he inhabits, he often possesses eyes that contain an extra iris, giving him a somewhat deranged look.

Personality
From his introduction, Nichinaga has been obsessed with destroying his brother, and seemingly the entire world in the process. His true motivation is far simpler: he wishes to take revenge on Tsukihisa for erasing his memories and stealing Suigetsu. Because the Shadow Organization was largely Tsukihisa's creation, however, Nichinaga wishes to see that destroyed as well. Virtually everything he does is for Suigetsu's sake, though even she does not realize this until it is too late.

History
As a young man, Nichinaga searched for a heavenly maiden able to grant wishes, in the hopes that she could take away his incredible psychic power. His search brought him to Ryusenkyo, where he met Suigetsu and convinced her to be his wife. They lived there for some time, but eventually began to travel at Suigetsu's request. They came upon a band of ability users, led by Tsukihisa. As the greater psychic, Tsukihisa erased and edited the couple's memories: he took Suigetsu for his own subordinate, and had Nichinaga assume the identity of Nichinaga Oumi, his older brother (supposedly so that even if a betrayal was discovered, Tsukihisa would be forgiven because they were siblings). Nichinaga co-founded the Shadow Organization with Tsukihisa (and apparently they had some input from Tokimori Hazama as well) around 400 years ago. Little is known about him until he assumed the identity of the King, and was surrounded by his servants and Michiru, who ran his Puppet Soldiers program. By making contact with Suigetsu, Nichinaga learned of his brother's many betrayals, and gradually became entirely consumed by revenge. He left his castle abruptly, taking two of his puppet soldiers (No. 0 and No. 3), Suigetsu, and several children (including En and Haruka) with him, effectively abandoning Michiru and the others, which became a source of great resentment for them.

From the Organization's Shadows
Nichinaga operates entirely from the shadows at the beginning of the story, never revealing himself, but his influence is still felt: Masamori is promoted to the Council of Twelve on his order. However, Nichinaga begins to take action against the Shadow Organization: he hires the Ougi Clan (Shichirou Ougi in particular) to eliminate Ichirou Ougi, Konozuka Kihei, and the Management Office. He also orders No. 0 to kill Okuni and destroy the Records Office. He orders many of these attacks from a cabin in the woods, where he stays with Suigetsu and Haruka. Nichinaga also sends No. 3 to Guillotine Island as a spy, where he observes the battle between Yoshimori and Yashiro, and collects Nichinaga's serpent from Yashiro's body after her death. Later, Nichinaga orders Three to Karasumori, with the cover assignment of assisting the Kekkaishi. During this time, Nichinaga stays in contact with Three via small demon messengers.

Hunting Yumeji
While Masamori Sumimura and Okuni speak with Yumeji Hisaomi at his home, Zero destroys the house in a hail of swords. After identifying himself to Masamori and confirming they are not technically enemies (Zero is only there to kill Yumeji, who is not necessarily Masamori's ally at the time), Zero loudly delivers a message from Nichinaga to Yumeji, taunting him and gloating over his victory. Masamori pursues Yumeji alone, still intending to join forces with him against Nichinaga, but Yumeji repeatedly proves untrustworthy, first attacking and binding Masamori with plants, and then trying to take over his mind. Masamori's Zekkai protects him, and he proves his resolve to change the Shadow Organization at any cost by entrapping them both in a Kekkai and threatening to collapse it. Before he can, Zero attacks again, killing Yumeji.

Battle at Hakuma
Nichinaga relocates to his former castle in Hakuma, along with Zero, Three, Suigetsu, and Haruka. Upon their arrival, they encounter Kakeru and No. 1, who had been using the castle as their base. Nichinaga knocks Kakeru into a coma with a psychic attack, and One has little choice but to take orders so he can watch over Kakeru. Later, Suigetsu and Haruka vanish suddenly, and Nichinaga orders his servants to find them. Unknown to him, Zero has locked them and Kakeru inside a hidden room in the castle that cannot be opened from the inside, and is invisible from the outside.

Tatsuki's resistance forces attack the Shadow Organization HQ, and Nichinaga's mind-controlled troops are sent out to defend it. Due to Nura Kidoin's complete control over her ogres, his psychic serpents are unable to control them, so the ogres quickly defeat and bind the Ougi men. In Hakuma, Nichinaga is confronted and mortally wounded by Zero, who reveals himself to be possessed by Tsukihisa. Tsukihisa explains how he survived Yumeji's death by attaching himself to a passing bird, and then possessing Zero before he left, and remaining undetectable to Nichinaga's mental scans. The two begin trying to kill each other, and Nichinaga recalls all of his psychic serpents in order to overwhelm Tsukihisa.

Masamori is tasked with killing Nichinaga, and finds him after Tsukihisa is defeated. Nichinaga, resigned to his fate, make no escape attempt, and tells of how he met Suigetsu and first fell under Tsukihisa's control. Suigetsu escapes the hidden room by transforming into a dragon, bringing Kakeru and Haruka with her as she confronts Nichinaga. After telling her of Tsukihisa's death, Nichinaga asks why she betrayed him. Suigetsu confesses that she only wanted to stop his plan to destroy everything, but that she had always been loyal to him, even while under Tsukihisa's command. She is shocked when she realizes that his entire plan was actually seeking revenge on Tsukihisa for her sake. Haruka uses her power to heal Nichinaga's wounds. Kakeru confronts him about the attack that put her into a coma, during which he passed on a psychic message from Michiru, in which she apologized for involving Kakeru in the horrible things she did in the name of saving the king. Nichinaga accepts blame for using Michiru, as well as her death, but in Kakeru's frustration, she purposely re-activates her world destruction spell. At that moment, the Gazer emerges with Tokine Yukimura, absorbs the spell's power, and takes the stolen shinyuuchi power from Haruka, causing her to collapse. Nichinaga desperately offers his life for Haruka's, but the Gazer refuses, until Suigetsu offers her life instead. Admitting that it has a need for the records Suigetsu's mind contains, the Gazer agrees to eat her instead, and returns a small portion of the power to Haruka before eating the rest.

Nichinaga uses his serpent to draw Tsukihisa (in the form of his starfish avatar) from Zero's body. He asks Masamori to look after the body he is possessing, and apologizes to Suigetsu for involving her, but she brushes off his apology, saying that she chose to be his wife. Nichinaga ejects himself from the body in serpent form, and drags Tsukihisa with him into Masamori's Zekkai over Suigetsu's protest, destroying both avatars.

Powers & Abilities
Psychic Powers: Nichinaga has considerable psychic abilities, and his psychic avatar takes the form of sea serpents.


 * Mind Control: Nichinaga can control others by placing one of his serpents into their body, where it essentially takes up residence, and remains until either removed or destroyed. He can even hide many serpents in a single victim, so that they in turn can pass them on to others, bringing them under his control as well. It is this ability which has made him the main antagonist of the series, and which makes him among the most feared individuals alive. He can almost completely take over another's mind, and when bolstered with Haruka's power, he is able to control an entire army at once. But he must strengthen his control over them regularly, or else risk his control fading.


 * Body Possession: Both Nichinaga and his brother are able to forcibly take over the bodies of others, transferring their own minds into a new body. They have survived this way for centuries, taking over other ability users in order to gain a second power. However, repeated use of this ability causes the memory of the user to gradually deteriorate.

As En
Spellcasting: The Sousui's final body of a young boy displays great skill with majinai or incantations, which is apparently the reason he chose it. In it, he created a huge circular charm, which was capable of transporting a large percentage of the suppressed Ougi Clan under his control, in order to take over the Shadow Organization Headquarters.

Dimension Manipulation: After Okuni's death, Nichinaga took possession of her seashell pendant, which she appeared to use as a focus for some of her techniques. He has been seen using the eye-shaped portals Okuni commonly used for viewing.

As King
Earth Manipulation: Though rarely seen doing so, Nichinaga could control earth while in the King's body, easily raising protective barriers out of the ground that are capable of regenerating rapidly if damaged. He lost this power when he abandoned the body, though the vessel remains locked away within his castle.

Suigetsu
Though Nichinaga is often cold and heartless, the majority of his actions stem from his deep love of Suigetsu and an overwhelming desire to avenge her cruel treatment by Tsukihisa. This is almost never evident, however, not even to Suigetsu herself, who lived in fear of his wrath.

Tsukihisa Oumi
Nichinaga is entirely consumed with having revenge against Tsukihisa, for numerous betrayals over the centuries, but chiefly for erasing his memories and stealing Suigetsu away.

Trivia

 * In the name Oumi Nichinaga, "O" (逢) means meet, "Umi" (海) means sea, "Nichi" (日) means date, and "Naga" (永) means forever.
 * En (遠) means far.