Coworker stares at me why?

I have this coworker (male) that I noticed that he would stares at me for some reason he done it like 4 times also stares at me when I'm working on something Also when I'm walking down a Hall way he would just look at me in my head I'm like why is he looking at me for

Also we don't talk really
Coworker stares at me why?
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