Sorry if I repeat again anything as you may read below.There is a great deal of info and fictional history I've considered in putting this story idea together.
There is a lot of room to chat and work things also to suit your preferences.

The vampires in general are a rather cool and elusive cousin to the homo sapiens sapiens. They evolved at about the same time as their human cousins, but retained their fangs for hunting, tearing flesh and more specialized nails that tend to grow like claws.
Their life spans were much much longer than the humans and as the overall theorized extinction of the neanderthal came about (which is a debate), the vampires stayed to themselves and are much smaller in number compared to their human cousins, as they are rather elitist and looks down on their cousins. As such, this led to repeated in-breading, causing a severe recessive gene to surface, anemia.
Later, as they were faced with extinction rather than breed with the humans, a virus passed through them and made them unable to consume food and could only digest blood, and only the blood of their cousins, humans, which they could consume of any blood type as long as their blood was strong and healthy. Also in turn, this created another side effect. Their already extended life spans were increased even more, for all eternity as their cellular degeneration slowed to almost nothing once they reached the age of 20 in their years... or 150 in human years. The average gestation period is about 5 years and siblings can be hundreds and even thousands of years apart.
They are unable to "turn" humans into vampires as they are a distinct blood line, They have an extra light bone structure and compensatory muscular structure, so it may appear to others that might see them, that they fly, though in fact it is long distance and strong jumps that give such an illusion and gives them the ability to do things that normal humans are unable to do. Their body mass is over all lighter and are divided in clans around the world, living in massive underground mansions, to keep their existence hidden, but for hunting.
Occasionally one will marry and breed with a human, and thus begins the elders supervisions of the children and their lineage. Watchers are assigned to them to follow there development to see if any of their kind sprout up. Then they must take them in and begin the process of refining their genetics so that only the children with their bloodline are the survivors and inheritors. They also have glands that can create a mucus type substance that allows them to climb walls and go places and do things normal humans also can't.
This is a result of their lymphatic system, which also carries a high amount of white blood cells and antibiotic qualities that allow extremely fast healing and close and coat, healing deep wounds. Limbs, arms, heads, etc can be lost and can therefore be a cause of death, unless it is quickly reattached within a very short period of time (again due to the mucus/ lymphatic secretions). They have night vision, so the day does bother them, but does not hurt them. They live underground in large extensively elaborate mansions and have the finest things to surround them as they are great lovers of beauty.
As time has passed, with evolution in play a bit... just like the mosquito hawk came to look and imitate their prey, the mosquitoes, so did the vampires, but being the most beautiful of them and breath taking to look at or be around. Their looks and demeanor are a tool for attracting prey. The parts of the brain that humans are said to have not tapped into, they have full access to and can read and project thoughts to each other and to humans.
They can also project images and emotions of love, ecstasy, passion, to calm and to soothe and be whatever their prey needs to make their hunt easier as well as feel and hear the thought and emotions of humans, to the point of having control over them when they really want to. They are fast, not able to be tracked by scent, unless it is by another vampire and excellent fighters with incredible strength. Their nails grow differently also, more specialized, hunter nails that grow like claws, almost completely unbreakable but by the maintenance of the covens years of refining techniques. They use these also for hunting and climbing, etc. When filed they are almost rounded but pointed in appearance. If allowed to grow naturally, they will shed layers but will grow talon like, arched and rounded...[/b][/i][/u]