Line line number 9 is a fun little trick to do to your friends. You start behind then and proceed to draw two lines, followed by the number "9", and then lastly two dots right on there back. After those steps have been completed you may give them an "electric shock" by tickling their ribs.
Once the trick has been initiated, NOTHING can stop it. Not even a shotty not.
Person A : "Line line number 9 dot dot electric shock!"
Person B: "Fuck off"