First appearances can be influential, but they're not the be-all and end-all of my opinion of someone.
If my first impression is that someone is a complete cock, that'll be a hard notion to displace. I rarely become friends with people who start out as prats.
However, aside from that, I give people the benefit of the doubt when first meeting them. Appearances rarely matter, except if it's someone who's ridiculously groomed and made-up and obviously very self-consciously declaring "OMG I AM SO BEAUTIFUL LOOK AT MEEEE". But that's got as much to do with body language as actual appearance.
I have no friends outside of this series of tubes called the Interwebz.
That likely speaks more than I can on this topic.
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