Zero Kiryu

Zero Kiryuu (錐生 零, Kiryū Zero) is one of the main protagonists 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.

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 (sometimes female vampires) although his cold nature scares most of them away. Hio Shizuka even stated that after meeting him as an adult that he had grown to become 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 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 one 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 to 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, or holds all the details about how vampires and humans can be similar in their own ways. As told by Ichiru to Kaien, Zero's favorite food is vegetable soup, but 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 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, 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 “tsundere” personality. He has a lot of attitude, is not at all impressed or easily controlled by higher class vampires, and 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.

History
Zero was born to a Vampire Hunter's family. Zero, along with his identical twin brother, Ichiru, and Kaito Takamiya, was 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 the still naive Zero made himself vulnerable to an ex-human vampire when his teacher turned wild and tried attacking Zero due to her Level E state. His teacher had ran away from an 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 although he was cold and hostile at times to 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 became friends and constant companions.

Plot
Main article: Plot Summary for Zero Kiryu

Powers and Abilities
Zero is a vampire hunter 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, 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 and when they become one he would become the world's strongest hunter. He then explains that he has drank the blood of Yuki who is now a Pureblood, just like Kaname and Shizuka which can make him become even stronger. After completing the fragment  Ichiru is now gone and bloody rose has become a part of his body.

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

Weapon
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 hooded ancestress 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. Which was later passed to Yuki Kuran when she became the school guardian and Zero Kiryuu when he became a vampire hunter respectively.

Yuuki 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 Hio Shizuka. 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 night 46  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 Night 87 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 Night 89  Yuki erases Zero's memories for her grand plan of sacrifing her life to turn Kaname into a human. At the ending of Night 91 Zero sucks Yuki's blood and regains his memories of her. Before he hands her over to Aidou, 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. Night 92 page 18  Zero told Kaname to fight alongside with him and face his feelings and not make Yuki cry anymore.

Kaname instead, takes Yuki and Zero by a suprise with his gesture when he told them that he wants them to be together. At the end of the manga after a long time skip, it was shown that Zero has already passed away. Yuki thanked him for the happiness he gave her and left to reawaken the sleeping Kaname from his slumber. Yuki has a daughter with Kaname and a son with Zero. Yuki's daughter was adopted by Zero as a foster father during the time her real father was absent in deep slumber after sacrificing his heart to the furnance.

Ichiru Kiryu
(When they were children,when their parents were still alive, and later in the series around the 40th night) 

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. 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 be born) So, now Zero 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 Hio Shizuka. 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 humor 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 Yuki)
 * "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 Yuki)
 * "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 Yuki) 
 * "Yuki, I...I only desired your blood, Yuki...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 Yuki)

Trivia

 * Zero japanese voice actor,Mamoru Miyano notable voiced Riku in Kingdom Heart Series a Action RPG game series develop by Square Enix.
 * Miyano also voiced Saruhiko Fushimi from the K Project Series.
 * Yuki, Zero and Aido are the only character who seiyuu voiced Anime K Project Series.