If you've ever had a girlfriend/boyfriend leave you and hook up with your best friend, you can be sure some dirty macking was going on while you were dating your ex.
John: "I'll be right back guys"
Dirty Mackin' Bob: "So Cindy, did you hear how John was talking to that slut Suzy when you were out of town? He doesn't appreciate you."
Cindy, John's Girlfriend : "Don't try dirty macking on me just cause my boyfriend's not here. Aren't you supposed to be John's best friend?"
John comes back and slams dirty mackin' Bob in the face with a shovel
When you meet a girl at a bar and end up fingering her at the bar or right outside the bar in an adjacent alley. It happens so quickly, it is practically during the introduction.
Person #1 - "Hey where did Mark go?"
Person #2 - "He is in the corner giving some bitch the Mackin Handshake"