The term Hunter refers both to a profession and to a specific race of people. Hunters are enhanced humans who have varying amounts of vampire genetic material in their DNA without actually being vampires. This is a genetic condition passed down from generation to generation, meaning that being a hunter is a hereditary profession.
As the name suggests, the hunter profession centers around hunting vampires. Part of their purpose is to keep the balance of power in the world between vampires and humans. They are frequently called upon to eliminate Level E’s or other vampires who have been deemed to be a threat to humans, although threat can sometimes be a broad specification and there is a general notion that “it is not a sin to kill a vampire”.
The Hunter’s Association is the main organization and governing body of Hunter society, under the direction of an Association President. Hunters are spread all over the world. The Association maintains a master list of vampires who have been slated for extermination and these lists are farmed out by location to individual agents in the field. Individual hunters are not always aware of the exact reasons for which a target is being hunted.
Hunter children are apprenticed at an early age to an older hunter who is responsible for their training from childhood up. Given that hunter genes run in the family, it is most likely that training often consisted of a mix of instruction from the child’s parents and from Master to whom the child was apprenticed - somewhat reminiscent of the training pattern often utilized by the Samurai.
The first hunters came to be thousands of years ago when they “ate” a pureblood vampire and gained the powers that would be passed down through the generations. One side effect of this, however, is the “twins curse” – hunters can never give birth to a healthy set of twins. One will almost always absorb the other while still in the womb. In the rare case that both are carried to term, such as with Zero and Ichiru Kiryu, one will always be much weaker both physically and as a hunter than the other as a result of having been partially absorbed.
Every now and again circumstances combine to create especially powerful hunters who, although still human, are more like vampires than other hunters, such as Kaien Cross (and probably Zero Kiryu had he not been turned). Hunters respect that power, but there is also a certain amount of distrust that comes with being seen as a “vampire without fangs”.
Hunters use special weapons that are made from a “mother metal” contained in a forge beneath the Hunter’s Association Headquarters. The method for creating this metal was discovered thousands of years ago by Kaname Kuran in his previous incarnation. It required a pureblood heart to be mixed with the metal - the only thing that would enable the creation of weapons that could kill their own kind. An as-yet unnamed pureblood woman sacrificed herself to provide both the heart for the metal, and the blood and flesh that started the hunter race.
Two of the first weapons forged were the Bloody Rose and the Artemis Scythe, now carried by Zero Kiryu and Yuki Kuran respectively.
The previous Association president was secretly in league with and accepting blood bribes from the Vampire Council and Rido Kuran. He was dispatched by Kaien Cross during the battle for Cross Academy and Cross currently holds the role of acting president of the Association, a responsibility which he shares with Toga Yagari.