Can you tell me what you know about vampires?

Vampires are graded, and the lower level generally lives by sucking blood. They can't be exposed to the sun, but pure blood species can suppress their thirst for blood. They are not afraid of the sun, but their ability will decline. Moreover, vampires have a strict hierarchy, and nobles usually look down on non-nobles and even civilians. People who have been bitten by pure blood species will be lucky to become advanced, especially those who are willing to be bitten by him, and he may surpass pure blood species. Also, there is no ethics between pure blood species. . . . . .