I am here speculating that the truth behind the vampire horror stories is a recognition that a deathless humanoid being must be a predator upon humans.
A similar fear has recently surfaced, although it was first envisaged in Mary Shelley's "Frankenstein", that we might be creating electronic monsters to take over the world from us humans.
We've been doing it for centuries, except the monsters are more abstract.
John Steinbeck says, in "The Grapes of Wrath", that part of what ate up the farmers of the Dust Bowl was the need to keep feeding certain man-made monsters, called banks. I am carrying his notion a bit further.
According to certain interpretations of the laws of the USA, a corporation possesses in law many of the rights of a 'natural person'.
We might conclude that this interpretation creates a species of the dreaded undead.
Certainly, there is no known natural limit to the lifetime of a corporation.
Worse still, as recent economic history shows, even a corporation that manifestly deserves to die may seem to damage its victims more if it dies than if it is kept alive.
With that example before us, what reason is there to suppose that any multinational corporation has any term limit upon its life? They die only of starvation, or by being killed. In this they resemble the mythical 'undead'.
It is my assertion here that we need a cadre of experts better than Dr. Van Helsing to assist us in seeing to it that world-spanning commercial corporations do not suck the life out of us mere humans.
The Roman Catholic Church is not a corporation, but it is officially a hierarchy, and it is clearly a bureaucracy. If you grant that it behaves like a corporation (I'll allow that it's a non-profit, since it has no shareholders) then it is perhaps the oldest corporation in the world, and I have no doubt that its members expect it to be immortal until no earlier than Christ's Second Coming.
Churches that claim to have access to life after death, and to the only recipe for attaining it, can hardly be surprised when their followers conclude that all contrary beliefs should be exterminated.
There is another class of deathless entities that prey upon humans to the point of consuming their lives.
They are called nations, and although they can be extinguished, it was wisely said of the best of them that the price of Freedom is Eternal Vigilance.
Men and women will kill other men, and women and children too, "for their country".
By comparison, hardly anybody has died "for Love".
We need to be watchful about what our own Nation is doing.