A rule for determining a woman's worth during a hookup. One finger is a gift from above, two fingers is a perfect fit, three or more and you've got a whore.
Jon: Let's see if the 3finger rule applies to Stacy.Can i finger you Stacy?
Stacy: Yes Jon.
Jon: Well meet me at my place around 9ish, you passed the 3 finger rule.
By Jaquelyn
The Finger Rule
The rule is a game, were you have to make an OK sign with your hands below the waist; If someone sees it then you can do one punch to them. If the person who sees it puts their finger in the hand and gets it out without being caught, they get to punch you 5 times.