I'm surprised he hasn't impregnated anyone

With the way he's seducing women left and right for who know's how long. Unless vampires are sterile, maybe a good sequel could have been made about one of the women Dracula ravished, like Maria, ending up bearing a child of his. There would be allot of conflict with the parents, if they chose to raise it. Plus, the child, a vampire or not, could end up like an evil, antichrist figure, or actually good but struggling to escape from the shadow of their lineage.