A favorite pastime of Urban and Suburban children.
The child will knock on an unsuspecting victim's door, but before the victim has time to answer, the "knocker" will dissapear in similar fasion to a ninja.
Tyrese: Yo brotha, let's go ninja knocking.
Tyrone: Wurd up dawg, ima say we get the ol' bitch down the alley.
Tyrese: Hellz ya mother fool