The article states that the boy's body was drained of blood. What do you suppose the black magic practitioners do with it?
Coincidentally, Voldemort, the chief practitioner of black magic in HP drinks the blood of a unicorn to gain some kind of power.
You could probably do a search on "Satanism + blood drinking." I don't have the stomach for it right now.
Actually I believe the blood is life sustaining, not a source of power, but that's beside the point.
But, for the record, he is the evil guy. And the drinking of blood is a bad thing. Harry does not drink blood.
Coincidentally, Voldemort, the chief practitioner of black magic in HP drinks the blood of a unicorn to gain some kind of power.
And everyone knows that Voldemort is supposed to be the hero of the book, not the villain.