Why does my guy friend constantly looks me in the eyes? What does it mean to guys in general?

We're long time friends. When ever we're together he looks into my eyes... for long. He does it mostly when we're alone. If someone is around he looks at me but then his eyes wonder to the other person (s) to see if they are noticing it and then get back to look at me.
If we talk about something serious he looks with less intense. If he tease me or we joke/banter he does it more intensely. When we sing together (we sing for weddings and in church) he keeps eye contact through entire song with few quick breaks of eye contact if he's doing something else. Again, if we're alone, but more careful if someone is around.
If I ask him why, he sometimes just smiles. Sometimes he says that we don't have to talk, that we understand each just by looking one another. That we talk with our eyes :)
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+1 y
I honestly believe the last one is the real reason🤦‍♀️😂
Why does my guy friend constantly looks me in the eyes? What does it mean to guys in general?
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