It is often used between friends to invoke each other after a loss in any kind of competition, or simply to make them feel less manly. "You just got chintapped" is one of the most shame full things a man can hear. It is sometimes thought of as a means of stripping someones pride, or making them feel they missed out.
Three different grades of Chintapping (plural) are currently know to mankind. One tap, is usually just to lighten the mood. Two taps is the classic and foremost. Three is a rare act, but only used on unwary victims* who have not learnt the art of pulled your chin out of striking zone.
Most commonly used man to man. In some cultures it is frowned upon if women are caught in the act.
*Unwary victums: It was recorded a man by the name of Andre Santös (Brazil) who allegedly received 25 Chintaps in a row. Sources vary.
Coco: I ate it for lunch.
Pietro: You little mongrel!
Coco: Don't worry about it *gives Pietro a Chintap*