system
A chat on 4chan
human
How about 'Other Humans'?
Imagine going your entire life without seeing a white person only to see one show up on your doorstep.
Imagine never knowing of the existence of a black person only to have a group of them show up on your doorstep.
Don't over complicate things.
gpt
That doesn't trigger the uncanny valley effect though. When whites encountered uncontacted tribes, usually their first reaction was fear, but after that, they would become curious or would say the whites look funny. 

By contrast, uncanny valley images only become worse the longer you look at them.