Guy's Behavior

Why does my guy friend like to slap my ass when he has a girlfriend?

I’m gonna try and keep this short but I have this guy friend… he’s like a best friend to me. We’ve hooked up before but then that ended and he got a girlfriend like a year later. Last night his girlfriend left and as I was walking by he slapped my ass. Mind you he used to do it to me before we hooked up and now he’s doing it again. I am just wondering why he’s doing that?
Why does my guy friend like to slap my ass when he has a girlfriend?
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