How do you make a person shut Up when he says, 'Oh, I saw you talk/laugh for the first time haha' everytime you talk /laugh?

Basically, I have this really annoying little fucker in my life who everytime he spots me interacting with people, says this. I've interacted with him very few times, so he basically doesn't even know me.

While I am a little introverted, no one likes this bs.