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Kou Mukami (無神 コウ Mukami Kou) is the second son of the Mukami household. He is an idol in the human world as a side job.



Kou has a handsome, beautiful face. He has blond hair with his bangs covering the top right side of his face. His left eye is light blue and his right eye is red. He wears earrings on both ears.

He usually wears a long sleeve black shirt that has circles in the front and black bordering the top and bottom. He sometimes wears it with a pink jacket with short sleeves. He wears it with blue jeans. He also wears a necklace and bracelets on his left arm.

His school uniform consists of the black school blazer with the sleeves rolled up to his elbow and a white dress shirt underneath that is slightly unbuttoned revealing a maroon shirt with four yellow diamonds on it. There are two red belts along the bottom of the shirt. He wears black pants that go up to his knee with long black socks with the right one having a vertical row of diamonds on it. He wears it with white boots that have some black detail on them. He also has a gold diamond-shaped necklace that has two curves sticking out at the top with a red jewel in the centre and two long strands at the bottom. He also wears bracelets on both arms.

In LOST EDEN, Kou's school uniform consists of the dark red school blazer over a pale yellow gym jacket and a white dress shirt underneath. He wears the black school scarf in a ribbon style around his neck which is fastened with a gold heart-shaped brooch. He wears black pants along with tall white boots.


He appears friendly, but he's actually very selfish and two-faced. Anything surrounding this idol Do-S (extreme sadist) is always at his mercy. He uses his handsome, beautiful face to his own advantage.

Due to his brutal childhood, Kou can easily switch his cheery and easy going usual appearance of a superficial person and an idol, to a vicious and very cruel merciless monster who doesn't understand at all, the very meaning of love. Thinking that all of the humans are vile creatures who either want to use and abuse, or be used if they are paid for that.


As a human child, he was abandoned in a manhole and never knew anything about his parents or where he had come from. In LOST EDEN, it was revealed that Kou was actually born into an aristocratic family. His parents were exiled during the war, and they were unable to take Kou with them. They entrusted him to a nanny who later abandoned him in a manhole when she was unable to continue taking care of him. Since he had spent most of his early life living in the sewers, Kou would always dream of obtaining the blue sky he saw above. One day, soldiers randomly shot a mother and her child in front of Kou, believing to be making them examples to potential rebels due to a war which was going on in the country. Kou didn’t understand what was going on or what the soldiers who found him intended to do to him. When they saw his face, they sent him to the orphanage. Upon arriving there, he received good food, clean clothes, and all the nice things he wasn’t able to have in the sewers. Kou thought of the orphanage as heaven.

Young Kou

Then Kou was taken to a "club" where he was whipped, cut, beaten and tortured, physically abused in all possible ways by the aristocrats. Due to the war, the country needed money. To earn quick money to fund the war, the orphanage selected and sent the beautiful looking orphans like Kou to those clubs, offering them up as merchandise and "entertainment" for the aristocrats. He was so in-demand that his bruises and wounds didn't have time to heal. Kou didn't want to think that his beating was painful, believing he should be happy because he could have nice things and it was also because he was repaid for that treatment. This caused Kou to grow up believing that the world is about "give-and-take".

Eventually, he accepted that the situation he was in was basically hell. In an attempt to stop the orphanage from making him continue as an aristocrat's toy, he lamented that his right eye might never see the blue sky he craved again. He decided to disfigure himself by gouging out his right eye. Unfortunately, that only made the aristocrats desire him more. Kou realized that he made a mistake, and he feared that his situation would only get worse.

Kou tried to commit suicide but realized that he was unable to kill himself. It was then when he met Ruki, who called him a loser. Kou denied that and tried to kill himself, (Ruki even dared him to) but again, was unable to do so, as Ruki expected. Ruki told Kou that the reason he was unable to commit suicide despite desperately wanting to escape his situation was because he still had hope. Ruki knew this because he often caught Kou staring at the sky. Ruki told Kou that if he gave up that hope, he would be nothing more than a loser. Ruki invited Kou to come with him if he wanted to be free from his hell and they became friends.

Kou, later on, met Yuma and Azusa became friends with them as well. The four planned their escape which was initially successful, but the orphanage staff caught up to them. Kou was shot and injured multiple times, but the staff didn't care, because Kou’s patrons liked him the more damaged he was. However, Kou was already near the brink of death by the time he was brought back to the orphanage, much to the dismay of the staff and the Facility Director. As Kou’s life faded, he cried that he didn’t want to die until he was able to see the free blue sky that he desired. Karlheinz soon appeared with the offer to make him and his brothers vampires if they agree to serve him.

Karlheinz turned the Mukami brothers into vampires, and gave Kou a new magic eye. His eye is and seems, to be like a jewel but it also allowed Kou to see the truth by reading the heart of humans. Karlheinz told him that he received the eye because he knew that Kou had trouble believing in other people besides his brothers and him. This would make it hard for Karlheinz"s "Adam and Eve" plan to happen if Kou was incapable of bonding. However, Karlheinz warned him to not to rely on the eye too much, as it would cause him to lose sight of what was really important to him. He also added that when Kou is matched with a certain blood and understands a certain truth, the eye would show him a miracle.

Although Kou doesn't completely understand the purpose of Karl's plans and experiments, feeling indebted for life, he plans to serve him unconditionally. Which later gives him many struggles when he realizes an impure vampire like him cannot become "Adam".



Even though not related by blood, the Mukamis are very close with each other. Kou respects Ruki very much and always listens to his advice. Kou starts to feel despair that he is failing Karlheinz in unable to become that Adam, fearing that everything until now is pointless and the goal won't be reached, at least not for him. His brothers stand beside him and remind him that no matter what happens he will always and forever have them and they will always be there for him. Their family is very important for them and they protect each other and always cover each others backs, having more close to human-like bonds, far stronger than the true vampires have.


Kou respects and obeys his savior and master Karlheinz hoping to serve him well, who has shown far more concern for the Mukamis than his own sons, even though in truth everyone for him is simply a pawn for his experiments. Karlheinz had given Kou's magical eye to replace his missing one.

Yui Komori

He was initially horrible to her at the beginning, such as making her fall victim to his fangirls after making out with her in front of them, or hurting her when she didn't follow his "give-and-take" motto. He also became frustrated when Yui pointed out that "money cannot buy everything" and resisted him. However, he slowly begins opening up to her after she finds out about his scars and his traumatic past. When he noticed that Yui was gradually starting to fall in love with him, he started "testing" her by constantly putting himself into danger to see "how far she would go" if she loves him. This resulted in him getting locked up in the dungeon as punishment for almost killing her. It was then when Yui decided to "test" him to see if he loves her which she did by almost slicing her neck. This was just enough for Kou to realise that he is in-love with her. In his Vampire Ending, he decides to betray Karlheinz by running away with her.

In Subaru's MORE BLOOD route, he appears more friendly and cheerful towards Yui, unlike in his own route. He also vowed to steal Yui from Subaru, no matter how long it would take him to do so. When Subaru started avoiding Yui, Kou took the opportunity to make advances towards her, but Yui rejected him as she was already in love with Subaru. This caused Kou to become jealous and he vowed not to give up. When Ruki asked him what attracted him to Yui, he replied "her blood", and Ruki told him that this was probably the reason why he lost to Subaru. It is then when Kou realised that he only caused a spark between Yui and Subaru, enabling them to get closer to one another. He also admits that his chest "hurts" at the thought of it, though he is comforted by Ruki. He approached Yui again and attempted to forcefully make her his, but Subaru interfered and they fought over her. In Subaru's Manservant Ending, when Subaru asked Kou what Yui is to him, he replied that she was a 'ticket' to enable him to become "Adam".

Subaru Sakamaki

He plays the antagonistic role in Subaru's MORE BLOOD route. He is rivals with Subaru; Kou being jealous of Subaru's privileged life, while Subaru believes Yui would be better off with Kou who has more "self-control" with his thirst for blood. Whenever Kou approached Yui, Subaru easily got jealous. Their rivalry with each other soon becomes rivalry over Yui's affections. In Subaru's Manservant Ending, Kou is killed by Subaru, after he kidnapped Yui in order to make one final attempt to become "Adam".

In his MORE BLOOD route, Kou provoked Subaru by biting Yui right before his eyes, in order to find out how Subaru felt to have his "bait" stolen. This resulted in Subaru punching Kou across the face before biting Yui in front of him as payback.

However, they soon start to get along with each other in DARK FATE and LOST EDEN. In their perspective LOST EDEN routes, Kou helps Yui cheer Subaru up in Subaru's route, while in Kou's route, Kou helped Subaru when he was gravely injured. 


Like all vampires, he has an inhuman strength as well as increased speed,(less than a pure born vampire), increased vision, hearing and smell. Being a vampire, he also heals at an accelerated rate though still slower than the pure-blood vampires.

Magical eye

Kou's missing right eye was replaced by a magical one by Karlheinz. The magical eye normally appears blue at first sight but when Kou starts reading the heart of the person, to see if they are being truthful, it starts to change to red. It also starts blinking from red to blue when Kou gets overemotional.


Impure vampires do not have the same amount of skills like pure ones, nor do they possess their own magic, however, Karlheinz borrows some for them, such as protective barrier and bat familiars.

However, due to being former humans, they are quite used to things like daylight and human food.


  • He calls Yui "Masochistic kitten" (M Neko-chan). In the English Dub, he calls her "Little Maso-kitty".
  • He is left-handed.
  • His foot size is 26 cm.
  • His right eye is prosthetic which was given to him by Karlheinz. It is also magical as it enables Kou to see into people's hearts - he can tell if they are lying or not.
  • He absolutely adores cats.
  • He is not very good at buttoning his shirts.
  • He obsesses over vongole bianco and can devour up to three servings in one go.
  • He is rivals with Subaru and likes to provoke him when it comes to Yui. His rivalry with Subaru eventually becomes rivalry over Yui's affections.
  • He has a birthmark in the shape of a lily flower, which he has to cover up during his idol work.
  • In LOST EDEN, it is revealed that his biological mother's name is Leona.
  • His real name is Emilio.
  • In CHAOS LINEAGE, he is a member of the Violet Family.