In my book, "aura" is interchangeable with "an abstract quality" and "athmosphere". A concoction of the subconscious, made from sensory data not available to the consciousness, telling you "this person can be trusted"/"this person eats babies". Ever noticed dogs barking at speciffic people for no apparent reason? I bet those seeing auras just eperience another type of synesthesia. Nothing spiritual in that.
I noticed I often paint auras around my characters, in a way.

It's been a very tired and unproductive day...

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