Ketsueki no teikō

Ketsueki no teikō, or Resistance of the Blood, is a natural resistance to disease and poisons. The cause is one of the components that make up the blood on the cellular level, though it hasn't been determined what component that is.

An added effect is that their blood also allows them to heal faster than other people. The healing rate is one fourth quicker than the average person.

If a person were to ingest the blood, it would have the same effect. But the effects of the blood would be dulled. The same thing would happen if the blood was applied to a wound.

The blood is most effective when in the body of the one born with it. Extracting the blood causes it to lose some of its effectiveness. It is thought to be a reaction when the blood is exposed to air.

It can be passed down from parent to child, but the percentage is higher for it to be passed down if the mother is the one who possesses it.

There are not many left alive with this blood since it was heavily sought after. Most were drained of their blood and disposed of once they weren't of use any more.