Roleplaying "Creepy", Astral Hazing, Nasty Vibe, Critter Spook... Options

[djinni]

How do you portray a character or NPC that is simply "creepy"
A character that has Astral Hazing, as a GM and player how does this impact the environment, what kind of creeped out feel does it impart?
do you feel it out as just an icky feeling? or is there a sense of forboding does the NPC (or player character) feel an instinctive urge to leave, does an awakened person hear a demonic voice commanding them to "GEEeeeEEeeET OooooUUUuuuUT!"
when around someone with a Nasty Vibe do the hairs stand up on the back of your neck? do you know "that guy" is just wrong? or does he just look at you wrong ALL THE TIME!?
Critter spook is not creepy by itself..you just smell wrong to an animal, perhaps you smell dead, or your pheremones give off the predatory scent.
however... combine it with the other two. someone who exudes a nasty vibe, spooks critters AND has Astral Hazing...
if that guy was astrally assensed...how would he look? how would the assenssor feel? would he have twisting writhing shadows all around him? would they twist into distorted faces begging for an "end" would the assensor recognize these faces? would it look dark and misty? like dark steam/mist rising from the earth around him?

the qualities I've found that might have an effect on how you feel around someone are as follows. please feel free to suggest those that are not here:
Astral Hazing
Nasty Vibe
Critter spook