Akira Nikaido
Human Form - Shin Form
Name Akira Nikaidō
Kanji 二海堂 昶
Romanji Nikaidō Akira
Race Human/Rei/Shin
Birthday December 11
Age 16
Gender Male
Height 175 cm (5'7)
Weight 57 kg (125 lbs)
Blood Type B
Affiliation Shirogane
Occupation Student then, Rei King
First Appearance
Manga Debut Chapter 1
Anime Debut Episode 1
Seiyū Daisuke Ono

Akira Nikaidō (二海堂 昶, Nikaidō Akira) is the main protagonist of Monochrome Factor. He is a teenager in his second year of high school who is also the reincarnation of Ryuko, a counterpart to Shirogane.


Human FormEdit

Akira nikaido monochrome

In his human form, Akira has gray eyes and messy light brown hair that travels down to the bottom of his neck. He has been seen in several outfits. His school uniform consists of a blue blazer, pants, a white shirt and black shoes. When he is not in school, he wears a yellow long sleeved shirt with dark pants. He also wears a black collar around his neck and has a silver hoop earring on his right ear.

Shin FormEdit

Akira Shin

Akira in his Shin form

In his Shin form, Akira doesn't change much in appearance, except for the fact that his hair turns black and his eyes red. He wears a buttoned up black shirt with two tails that end above his knees over a long sleeved white shirt. He has red pants and knee high black boots. His upper right leg is bandaged and he appears with two daggers which he uses as his weapons when fighting against Kokuchi. As the series progresses, the daggers later turn into a larger and more complex set of blades.


The new weapons of Akira.

Royal Rei FormEdit


Akira when he obtains Ryuko's inshi. (Royal Rei King Akira)

The final form of Akira in the manga. He retains the the black hair (but longer) and red eyes he has in his Shin form, but his clothes change. It is switched with a white military coat over an extended version of his Shin coat and a red shirt. He wears a black collar with a silver cross, black boots, and a white cape with red trim. His daggers become one large blade.


Akira's favorite colors are black, white, red, silver, and he favors all kinds of cats as well. His favourite type of movies are range from the 70's to the 90's. Akira also prefers electronic or techno music.

Akira has a somewhat dark and morbid personality, usually commenting or suggesting ideas that relate to extreme harm and possible death. When this is pointed out, he usually displays an uninterested expression. Akira is also known to be quite a slacker and once stated that he only attends school because he's just bored. Still, he does show that he's intelligent in terms of academics, but is talented in many different sports.


Due to Akira's appearance to have "stood out in a bad way", he is always involved in fights with either upperclassman, thugs, or delinquents and prefers to be alone. He always skip classes, hanging out on the rooftop until Aya Suzuno comes in and tries to drag Akira to class.


Kengo AsamuraEdit

Akira and Kengo are best friends, despite Akira often berating and abusing the blonde. It's commented that the relationship looks more like Master and Servant. He and Kengo have a close relationship with Kou, they both call him "Kou-nii".


Aya SuzunoEdit

Being a member of the disiplinary squad; Aya is often assigned to drag Akira back to class. Although she treats Akira rather harshly, she does care about him on a friendly level. She once harshly lectured Akira on the difference between a fight and a brawl, saying that Akira has to put more resolve into the way he fights or he'll be killed.


At first, Shirogane and Akira's relationship was untrusting. After Akira let Shirogane transform him into a Shin, it seems they both tolerate each other presence at most. When Shirogane betrays the group, Akira fights him in order to force Shirogane to accept him as his new counterpart. Because the anime is classified in the shounen-ai genre; Shirogane is more flirtatious with Akira and in episode 18 (Shadow of Encounter); Akira shows jealousy towards Lulu for going out on a date with Shirogane. Shirogane kissed Akira in the first episode of the anime while Akira was being turned into a shin.


Akira sees Kou as an older sibling, calling the elder "Kou-nii" even after Akira achieves his status as Direct Rei King.


Ryuko is Akira's predecessor in the line of Royal Rei Kings. They only met once in chapter 50 (volume 9), when Akira killed Hiryu and Ryuko showed Akira his memories. After their meeting ends in chapter 55 (volume 10), Akira obtains Ryuko's inshi; thereby becoming the new Royal Rei King.

Before the SeriesEdit

Ten Years AgoEdit

When Akira transferred schools; he met Kengo Asamura. Kengo was struck in awe of him and watched Akira from afar until he was called over by Akira and made his intention to befriend Akira and his curiosity of Akira's book clear. Akira made a bet with Kengo. The latter can borrow and read the book, but he has to write a 200 character summary of his thoughts. Also, Kengo cannot speak to Akira if he doesn't finish. Kengo eagerly accepts, only to find out the book was in English instead of Japanese.

A few weeks after that, Akira berates Kengo for his stupidity; proclaiming Kengo lost all rights to speak to Akira when Kengo failed to mention anything related to the book. When Kengo questioned Akira coldness toward others, Akira simply said that it was annoying and told Kengo to stop following him; questioning why Kengo doesn't play with the other children. Kengo said that everyone hated him and Akira gave a comment that he was annoying, but Kengo denied it and started to open himself by speaking of "weird things will happen" when he's around supernatural phenomenon caused by the Kokuchi. Akira demanded what Kengo had meant, but Kengo decided to change the subject. Three bullies from Akira and Kengo's class appear. The leader, Aizawa and his two lackies behind him claims the space that Akira and Kengo were occupying were their hangout then said it was "cursed", due to Kengo presence and tells them to leave.

Akira, who hated taking orders, steps up and said the area doesn't belong to anyone and it technically belongs to the city. Later, he then asked who they are since he never interacted them. He engaged in a fight with the three bullies and easily victors, showing off his fighting capabilities. After the fight, he saw Kengo beaten up and crying and asked if that is the first time he ever been beaten up. Not receiving an answer, he left. The next day, Akira is walking to school, thinking that Kengo will stay away him from now on and pondering that his peaceful school life is gone now. That is when he hears Kengo, his bandaged up face ever optimistic and catching up to him. Akira concluded Kengo as a "M" or "Masochist" and told Kengo to stay away from him as Akira made a run to school, both passing by Sawaki.

Two Years AgoEdit

Akira and Kengo are both now in high school as first years or freshmen.

The relationship between Akira and Kengo has improved, but Akira still treats Kengo like a servant and Kengo still keeps his optimistic attitude even when when beaten up. During small conversation, they bump into some delinquents that demanded cash from them. Akira, not wishing to get into a fight nor do as they say tried to drag Kengo away and ignore them. Kengo, on the other hand, acted rashly and punched one of the delinquents in the face. Kengo grabs Akira and runs away.

Both hid in the abandoned factory district from the delinquents for the whole day. Akira is about to leave when he notices something odd about Kengo. He is about to search for help when Kengo grabs his ankle and throws Akira through a wall. He is then choked by Kengo, coming face to face with a Berserker/Kokuchi Kengo for the first time. At this point, Kou intervenes and kicks away Kengo, saving Akira in process. Kou is shocked when he turns around to see Akira, nearly mistaking him for Ryuko. Akira; thinking Kou to be hurting his best friend, was about to attack Kou, but the Rei placed Akira under a sleeping spell or hypnotic sleep, knocking him unconcious and wiping his memory of this incident.

Akira wakes up when a Kokuchi was above him, saliva dripping onto his hand. Then, we see him with Ryuko possessing him and stopping Kou from using a suicide attack. After, Ryuko engages Kengo in battle and assuring most of the darkness has been removed, Ryuko reverted back to the unconscious Akira with Kou swearing to Ryuko he will protect Akira.


Akira mentions that he and Kengo met Kou when they were 10 years old when Kou had saved them from a group of delinquents after them, but it is not explicitly shown in the anime of what really happened in the past like the Manga.


Powers and AbilitiesEdit

As a human, Akira possess higher-than-average intelligence, mastery of athletics, and is a capable fighter.


Due to his contract with Shirogane, Akira becomes a Shin in the beginning of the series instead of a Rei.

Weapons - Akira used twin daggers till they were broken against the fight with Nanaya. Later on, the daggers changed shape to a more complex set of blades.

Superhuman Abilities - As a Shin, he has enhanced strength and speed. he can also land perfectly uninjured from a leap off the 5th story floor.


After defeating Hiryu and obtaining Ryuko's inshi and memories, he awakens as the Direct King of Rei.

Weapon - Both twins of the evolved version of his knives became one large sword and Akira can swing it with ease.

Abilities - Inheriting Ryuko's Factor, Akira gained abilities to control ice and cold currents, even controlling water when the ice is melted and setting up a "experiment" with the oxygen, giving him the advantage in his fight with Shirogane.


  • "Fair warning: You're dead meat." Adapted from Monochrome Factor Manga, Chapter 13, page 21
  • "I have to fight. I need to fight to validate my existence. I need them to recognise me existence, so that I can continue living in this world..." Adapted from Monochrome Factor Manga, Chapter 63, page 4


  • His hair is really soft and will mess up easily in high humidity (shown in the first volume).
  • His least favorite food is red bean manju, but it's what he usually eats for lunch (along with a carton of juice).
  • He loves all kinds of cats and is shown to be jealous of Kengo (shown on 4-panel koma on the sleeve of the first volume in Japanese) when a cat runs away from him but lets itself be pet by Kengo.
  • Akira character song "Destiny" is sung by his Seiyuu, Daisuke Ono.
  • Akira is also one of three characters to be shown on more than one volume cover. He is on the covers for volume 1 and volume 11.