The few human parasites and predators that I've watched, do seem to have some give away clues.
The eyes and the un flinching predatory stare as they lock onto and study potential prey for weaknesses, like a cat watching a mouse or a small bird.
There are no laugh lines around the eyes, the lower lip is relaxed perhaps even loose, the ones that I've watched, which are probably middle functioning ones, don't seem to smile to indicate any friendly intent.
There seem to be exploratory verbal jabs and intrusions into personal space, that seem to be intended to elicit responses so that they can be guaged. There are also blankings and back turning snubs, to see how we respond to being treated like worthless shit.
In the early stages at least, they are deniable. With a skillful narc, everything is deniable - the doubts in your own mind feck you up far more than any certainty would. They see what buttons elicit what responses.
I'm with
@Kaia, that I don't think there are any lessons that were failed.
The posture and gait, the facial expressions and the spoken responses of someone who is down, all convey what is going on with them.
someone with poor boundaries will come accross that way to anyone who is paying attention, and predators pay attention.
The narc that I went on the road to avoid in October, seemed to watch my father and brother's attitudes to other people, to guage who he could get away with verbally attacking and physically menacing in their presence. He also escalates to threats and implied threats of physical violence and uses invasion of personal space and physical menacing, rather than having measured responses to what he perceives as slights (incidentally, I've suggested to my brother that he watches some of Sam Vaknin's videos to see if they ring any bells for him, before he asks the narc to explain his thieving. - I don't think confronting the narc will turn out well, his entire monologue (it's not a conversation) seems to consist of boasting about his wonderful retorts to people who questioned or doubted him).
There are people who for what ever reason are drawn to narcs and psychopaths. I've only realized in the past few weeks that the same sex relationships I had, were with some fairly narcissistic arseholes, I go for much nicer females than I ever did males, and it is something that I am not anywhere near to understanding yet.
I think that narc parents also train their offspring to serve them. My father's father was a particularly manipulative and game playing individual (perhaps more neurotically obsessive compulsive and controlling than narcissistic - he used to love trying to put me in what he considered "my place", in front of other people), perhaps he trained us to look up to narcs, and to see narcissistic traits as normal? if so it would explain the apparent blindness to the thieving narc.
