Zero Kiryu

Zero Kiryuu (錐生 零, Kiryū Zero) is one of the main characters of Vampire Knight and the only Vampire Hunter/Vampire in the entire series. Zero is Yuki's childhood friend and the only other Cross Academy Guardian. As a Vampire Hunter, Zero wields the Bloody Rose as his main weapon, an anti-vampire gun. He is the father of one of Yuki's children and the adoptive father of Kaname's child.

Appearance
Zero is a tall, lean-built young man with silver hair and lavender eyes, the latter varying in shade from the manga to anime. Zero is a casual dresser, as his clothes are picked out by Yuki, and is usually wearing his school uniform incorrectly with the vest and red tie exposed from under his black jacket. He also wears five silver earrings; three on his left ear cartilage (top) and two on his right (bottom). Zero bears a tattoo, the Hunter's Seal, on the left side of his neck originally used to suppress his vampire side, and later used to tame him. He has grown muscular and taller as the series progresses.

Zero is considered to be attractive by the girls from the Day Class (as well as some female vampires) although his cold nature scares most of them away. Shizuka Hio even stated that after meeting him after he had gotten older that he had become very handsome.

Personality
Zero is generally a composed person, though occasionally he can act with coldness and hostility, especially towards Kaname. Though he appears otherwise, he is a gentle and kind person. Due to his childhood, he builds barriers around himself, rather than opening up to Yuki when they first got to know each other, a trait that is still evident even in the latest chapters of the manga. Yet despite this, he has a kind heart which longs to protect humans, and will never betray the ones he holds dear.

As a child, Zero was once a quiet and gentle boy, to the point that Ichiru questioned whether or not he was even capable of being a vampire hunter. However, after Shizuka's attack, Zero developed a strong hatred towards vampires. Zero is a tsundere character; he sports a scary aura that makes most of the Day Class students wary of him. He can also glare in a way that even Kaname Kuran calls scary. However, his innate nature is to protect humans, and his cold attitude towards those he loves is likely to push them away and keep everyone at a distance. He also happens to be a stickler for details, as he doesn't consider himself as an adopted son of Kaien's family with Yuki, and he lists all the ways that vampires and humans can be similar in their own ways. As told by Ichiru to Kaien, Zero's favorite food is vegetable soup, but he also enjoys shio ramen.

Following his full awakening as a vampire, Zero harbors a great disgust towards himself because of his inability to control his hunger and reliance on Yuki. His dismal outlook on his future and fear of what he might do if he becomes a level E causes him to give up and he almost kills himself with his anti-vampire gun, the Bloody Rose, but Yuki arrives just in time to stop him. He would rather ignore his hunger to the point of starvation before going to Yuki for help. He tries to help Yuki resolve her own problems and then impresses upon her that its alright for her to burden and use him because she owns him.

Zero is hostile towards the Night Class vampires when they threaten him, however he adopts his standard tsundere attitude when engaging them one on one, retaining a level of civility. Zero expresses a great deal of anger towards Purebloods because of their mechanisms in his life in particular, and because of this, he extends this hostility toward Yuki as well after she turns into a Pureblood vampire. In spite of this, his sense of duty overrides his issues, ensuring his reliability and trustworthiness.

A gifted hunter who is intelligent, athletic, and good-hearted, Zero nevertheless has a difficult time thinking of himself or any other vampire as anything but a monster. He struggles both with his desires for blood and in the latest chapters, his equally strong desire to kill vampires. Because of all this, Zero can be very closed off, as well as being difficult to understand or get close to, especially since he has a habit of not expressing his true feelings. He hides his true feelings behind a cold, composed personality. He has a lot of attitude, is not at all impressed or easily controlled by higher class vampires, and he also carries a positively burning hatred of all Purebloods. He often acts as if he doesn’t care about anything in order to hide all the scars and pain inside him that have nowhere to go. When not about his duties or in class, he can frequently be found in the Cross Academy stables with the fiery horse, White Lily, with whom he seems to share a special affinity. He is also quite a good cook which was admitted even by Aido, who is known for being quite picky.

History
Zero was born to a Vampire Hunter's family. Zero, along with his identical twin brother, Ichiru, and Kaito Takamiya, were trained as a vampire hunter by Toga Yagari who frequently looked after the twins when Zero's parents were out hunting. Yagari lost an eye protecting Zero when his teacher turned wild and tried attacking Zero due to her Level E state. His teacher had ran away from her aristocrat. This was Zero's first lesson on the danger of seemingly innocent vampires. Zero promises Toga Yagari that he will never regret losing his eye to protect Zero.

Four years ago, Zero and Ichiru found Shizuka Hio sitting in a tree, whom Zero immediately recognized as a vampire and told Ichiru to stay away from her. A few days later Shizuka attacked his family. She bit Zero and killed his parents; Zero passed out believing she had killed his brother as well.

After that attack, Zero was taken in by Kaien Cross to stay in Cross Academy. Yuki approached him carefully and cared for him despite him being cold and hostile towards her. Zero gradually grew affection for her but kept it to himself due to her love for Kaname Kuran. Zero failed to reveal that he was going to turn into a vampire after Yuki said she was afraid of all other vampires. Over the next four years, the two become closer but not on a level they could call each other friends.

Plot
Main article: Plot Summary for Zero Kiryu

Powers and Abilities
Zero is a vampire hunter who was chosen by Kaname to become a Pureblood killing machine. Zero possesses the standard abilities to sense vampires from a far distance, accelerated healing and in spite of being a vampire, is also able to wield anti-vampire weapons. Since he became a vampire, Zero is able to distinguish Purebloods from other vampires and has gained improved healing abilities. Kaname tells Zero that after he eats Ichiru, he would become the world's strongest hunter. He then explains that since he has drunken Yuki's blood and because she's a Pureblood, just like Kaname and Shizuka, it has made him even stronger. After completing the fragment, along with Ichiru now being deceased, Bloody Rose has now become a part of his body, growing veins that can easily kill vampires; but it requires either his blood or other blood to do so.

Zero's beast form made its first appearance in 40th Night after he drank Ichiru's blood and it's shadow was seen on the wall. In 82nd Night, the beast form is released in a new attack from Bloody Rose when Zero fights Kaname shortly after drinking Sara's blood.

Bloody Rose
The Bloody Rose is an anti-vampire gun that Zero keeps behind his school uniform blazer. Zero is able to transform his gun, Bloody Rose into its evolved state, after consuming his twin brother, Ichiru. Bloody Rose literally becomes a part of his body. However the cost is using a high amount of his blood. In the manga and anime, Zero had used Bloody Rose to kill Rido. It is  Zero's main weapon throughout the entire series.

Origins of Bloody Rose
Bloody Rose was a weapon born from the sacrifice of a Pureblood vampire, The Hooded Woman, 10,000 years ago. Artemis and Bloody Rose were originally Kaname Kuran's personal weapons during the wartime before he gave them to Cross Kaien to be in-charge. They were later passed down to Yuki Kuran when she became the school guardian and Zero Kiryu when he became a vampire hunter respectively.

Yuki Kuran
Yuki Kuran and Zero Kiryu became friends after Zero was sent to live with Kaien Cross who became his adoptive father after the murder of his parents by a Pureblood vampire Shizuka Hio. Both Zero and Yuki have a past with vampires making them both understand each other a little more than the other Day Class students. Whenever Zero has nightmares of the incident that day, Yuki would pat his head until he finally falls asleep. Though, Yuki was not aware of his growing feelings towards her except for Sayori who noticed. Zero knows that Yuki has feelings for Kaname. Zero reveals his romantic feelings towards Yuki in 46th Night  He asks her if the human Yuki he once knew is still inside her and after she replied, he gives her a kiss goodbye. Letting go of her, he told her that when the next time they meet, he will kill her. She replied by saying she will keep running away from him.

It is even said by Yuki that she must hide a part of her heart regarding him before leaving with Kaname, and that part of her heart belongs to him, implying that she may have feelings for him or have unconditional concern as that all his beloved ones are gone. Due to Zero's hatred for vampires, it is impossible for them to end up together. She still continues to defend him even though the relationship between them is very strained. In 87th Night Zero relieves his feelings for Yuki at the masquerade ball and kisses her. As they kiss they recall their time spent together growing up and both question why things had to become like this, where they both had to become enemies.

With the masks on, she is the human Yuki and he is the old Zero, just like in the old times. Zero dances with Yuki and ends it with a short tender kiss - which did not last when Kaname, their target stepped in, looked over at them and vanishes. As seen in 89th Night  Yuki erases Zero's memories for her grand plan of sacrifing her life to turn Kaname into a human. At the ending of 91st Night Zero drinks Yuki's blood and regains his memories of her. Before he hands her over to Aido, he comments that he had been afraid to face his true feelings, but not anymore. After gaining back his memories, he no longer feels hatred towards vampires like he once did and is seen to be standing next to Kaname in 92nd Night Zero told Kaname to fight alongside with him and face his feelings and not make Yuki cry anymore.

Kaname, after throwing his heart into the furnace, embraces Yuki and Zero and tells them he wants the two childhood friends to become a couple. After that, Kaname "dies" and Yuki runs out to stop the fight between vampires and vampire hunters. Then later on, we find Yuki in front of Kaname's ice coffin with Zero at her side. Zero embraces Yuki and tells her that Kaname's death isn't her fault and that she shouldn't feel guilty.

Zero then asks Yuki to be with him, saying "I won’t run anymore. You too, it’s fine for you to take your time thinking about it. Because knowing you, you’re still blaming yourself anyway. Damn. Forget that. Say that you’ll be with me. No matter how many years it takes, no matter how many decades pass… till this hunger turns me to dust. Say it to me.” - Zero Kiryu

It is hinted that later on Yuki and Zero become husband and wife. (This idea is further supported when Yori asks Zero in the Vampire Knight bonus chapter when she will recieve an invitation to their wedding.)

Near Vampire Knigh't end, Yuuki is seen infront of a headstone with a broken piece of the Bloody Rose in her pocket. One millennium (1,000 years) has passed, and Zero Kiryu has passed away. Yuki talks to the headstone, a metaphorical representation of Zero, and thanks him for the happiness he granted her. Yuki leaves the graveyard, a bright smile on her face, and heads to reawaken Kaname by sacrifing her life. She is repaying the debt she has to Kaname and granting him the human life he gave her. Kaname awakens as a human with Yuuki's two children (both left unnamed) at his side, and is left to explore the human world without his memories as a vampire.

Yuki had a daughter with Kaname and a son with Zero. Zero becomes Yuki's daughters foster father, and is later on held at the status of her "real father" because he raised her in Kaname's absence.

Ichiru Kiryu


Ichiru was the younger twin brother of Zero. Since they were twins born to a Vampire Hunter family, Zero and Ichiru were the cursed twins. To Zero's discomfort Ichiru often questioned in childhood why he was born since it was obvious that Zero was the one who should have eaten him in the womb. The older twin would scold Ichiru for his self-loathing and try to comfort him. However, Ichiru's feelings of jealously and despair continued to grow until Shizuka appeared and offered him a means to escape his faith. Zero watched his twin in devastation as Ichiru ordered Shizuka to murder their parents and leave him to live. Now the hunter is torn between love and hate for his younger twin. Eventually it is learned that despite his conflicting feelings toward Ichiru he still loves his little brother. Before the war with Rido Kuran, Zero ate Ichiru (another meaning for taking in Ichiru Kiryu's blood so they would be one like how they were supposed to before they were born) Zero now has Ichiru's strength and skills inside him.

Shizuka Hio
The Pureblood Shizuka Hio became Zero's master after she bit him the night of the attack on his family. She claims she did it because Zero reminded her of her former lover, a level E vampire that his parents killed. Shizuka meets Zero again four years later at Cross Academy while hiding in her hostess body, Maria Kurenai. Despite concealing her presence, Zero recognizes her. During a confrontation with Shizuka, she begins to taunt him about being his master. Despite Zero's hatred for her for her strongly remianed, he finds himself unable to go against her commands.

After watching Yuki getting threatened by Shizuka, he breaks away from her influence and manages to wound her. Shizuka escapes, but Zero is prevented from chasing her by a distraught Yuki, who'd previously realized that Zero had planned to sacrifice his life in order to kill Shizuka. Before allowing him to go, Yuki makes Zero promise to return after taking care of Shizuka. However, to Zero's shock, by the time he arrived to Shizuka, she has already been dealt the final blow by Kaname, who had been waiting for her in the wings. Though Kaname was the one who murdered Shizuka, Zero was blamed for her death by an angry vampire council.

Kaname Kuran
Zero disliked Kaname on sight recognizing him as a Pureblood vampire, like Shizuka Hio. Kaname has been his rival ever since. They are only tolerant of each other for the sake of Yuki Kuran. Kaname can be often seen jealous of Zero when Yuki expresses care for him. Another reason for Kaname to hate Zero, is because he took what was supposed to be his, an example is taking her blood. Kaname finds humour in taunting Zero, who is easily agitated around the vampire.

By the end of the manga, both men have made amends to a certain extent.

Quotes

 * "They are beasts in human form!" (To Yuki)
 * "I feel like...I'll go mad ...if I'm not hunting vampires during the night." (To Yuuki)
 * "They're beasts in human form! How can you trust them? Tell me!" (To Kaien)
 * "Are you going to let me live, Kuran?" (To Kaname)
 * "Drinking blood on school ground is prohibited. Perhaps you were drunk with the sweet smell of blood, Aido." (To Hanabusa)
 * "I am not your adopted son! You may have cared for me, but I did not allow you to ADOPT me!" (To Kaien)
 * "Don't talk about my parents like that!" (To Yagari)
 * " If you go one step ahead of me, I'll make you cry. " (To a Day Class Girl)
 * " Listen up, brats! Get the hell back to your dorms! Why do I have to deal with you running around screaming "Kyaa! Kyaa!" every damn day?! Why?! " (To the Day Class Girls)
 * "You'd probably wish to have your blood drank by Kaname-senpai, right? " ( To Yuuki)
 * "You heard it too? The sound of your blood being sucked in by me. After such a hair-raising experience you can't act as if nothing has changed. So don't interfere anymore." (To Yuuki) 
 * "Yuuki, I...I only desired your blood, Yuuki...I want it so much that it's unbearable to the point that unless I drank from you until the very limits of your life, I wouldn't be satisfied...such a disgusting, gluttonous greed...that is...the type of creature I am isn't it...?" (To Yuuki)
 * "Ichiru told me to live... and fulfill my goal. But I was afraid..All this time...I haven't faced my true feelings. I won't hide behind excuses anymore." (To Yuuki)

Trivia

 * Zero's Japanese voice actor,Mamoru Miyano voiced Riku from the Kingdom Heart Series, an action rpg game series developed by Square Enix. Miyano also voiced Saruiko Fushimi from the K Project Series. He also voiced Tamaki Suoh from Ouran High School Host Club and Ichinose Tokiya from Uta no Prince sama.
 * Yuki, Zero, and Aido are the only character whose seiyuu have also had roles in the Anime K Project Series.
 * Zero's English voice actor is Vic Mignogna, who has also voiced Edward Elric from the Fullmetal Alchemist anime as well as Yoshimori Sumimura from the Kekkaishi anime.
 * Coincidentally, all three characters have a parent(s) who is not present during a large part (or all) of the storyline. Zero's parents were killed, Yoshimori's mother is rarely home (to the point that other characters call her a bad mother) and Edward's father left him and his brother while they were children, with his mother dying soon after.