Pure blood

History
A Pureblooded is vampire that has no trace of human blood in their ancestry nor has it been tainted by the blood of average vampires. They are the most powerful type of vampire, but are only a very small portion of the vampire population. Marriages are focussed on keeping the family and bloodline pure and because of that it's not unheard of, for siblings, cousins and other family memebers to marry as it is essential to keep the bloodline pure. Another option is to marry a member of another pureblood family.

Shizuka was originally Rido Kuran's fiancée, but they never married due to his disappearance and finally her death.she loved a former human vampire but was killed by a Kiryu vampire hunter.she never bitten ichiru because she knew he was in love with her.

Purebloods are treated like royalty mainly because of their power and rarity, and because of this, purebloods are considered "treasures" by the Vampire Council. The Council hold Pureblood's powers in extremely high regard but fears their powers especially the power that lets them control lower vampires. It is taboo to kill or to even harm a Pureblood. Other vampires lust for a pureblood's blood, more than their lover's making them the perfect prey whom they try to hurt with words.

Purebloods live longer then most vampires, so, a pureblood can not die of illness or any other cause. They can only die if they commit suicide or are murdered by another Pureblood or a Vampire Hunter. It's said that most purebloods kill themselves because of the long lifespan a pureblood lives. There are only seven pureblood families left: Kuran, Hiou, Shirabuki, Ouri, Hanadagi, Touma and Shoutou. Before the birth of Yuki Kuran who is youngest pureblood at the age of 17, their were thirty three Pureblood vampires of which the Vampire Council controlled nineteen of them, the rest on them had been away for a long time.

It appears that the Kurans are the most powerful pureblood families.

Pureblood Abilities
Pureblood vampires have many unknown abilties. Some that were shown were posession of other's bodies (possibly only relatives) and the formation of those bat like creatures, as used by Rido and Kaname. It appears that purebloods tend to specialize in one particular power they choose. In the anime and manga, it seems that Rido Kuran posesses the ability to morph his own physical body while his brother Haruka can morph the physical forms of others. In the official fanbook, it was stated that although Shizuka Hio never exhibited it, she particularly excelled at plant manipulation. Some theorize that is where Zero Kiryu's ability to control those vine like things came from.