Of fangs and maid outfits...
In the field of behavioral psychology, there is something called classical conditioning.
Classical conditioning is a form of associative learning that was first discovered by Ivan Pavlov. Classical conditioning, when put into layman's terms, makes one think of "Pavlov's Dog". The idea behind Pavlov's Dog is that the dog would automatically salivate in the presence of meat powder, but that if the presentation of meat powder became associated with another form of external stimuli (such as the appearance of the person who typically feeds the dog), then that other form of external stimuli could, in and of itself (separate from the presence of meat) cause the dog to salivate.
Pavlov took observations like the one above pertaining to dogs, and used them to formulate classical conditioning.
