Guy's Behavior

If your crush shows up with a hickey, how would you react?

I've known this guy for 4 years. I thought we were crushing on each other other hard recently. I don't know what to think. He has done stuff to make me jealous, but I'm not sure this time. I saw his neck and hickies but they were gone the next day. My sister says it still puzzles her even with makeup that they disappear. My friends say it was probably makeup. He works over a hot grill. She's says it's probably waterproof. How can that stay on when your sweating to death.
When I called him on the hickey, I was devastated, turned around and walked away. He chased after me and I pointed again to his neck and he said twice smiling "what"? I said "get out". He said "so that's it". I said yes. My friend thinks their real and not fake. I can't understand what he would ask me "what?". He should know if I'm pointing at his neck. My friend says we are not committed so I can't get upset but I'm heartbroken.
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+1 y
I want to clarify that I've known him 4 years but never noticed him like that until recently.
If your crush shows up with a hickey, how would you react?
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