1 definition by Spencer Hills 101

Not for the faint of heart. When one roommate openly wrongs another in a irreversible fashion, the victimized roommate is then entitled to cause severe emotional and physical stress by slapping his roommate at an unruly time in the wee hours when he is sleeping. Note* the roommate doing the slapping is to do his best to make the other extremely paranoid, vulnerable, and scared to the point where his roommate will not get to sleep for an extended period of time. The person receiving the slapping may cuss, threaten, and even plea with his tormentor and would-be assailant to avoid the malicious attack. However, these wheelings and dealings must fall on deaf ears, as the aggressor mercilessly makes good on his the threat.

The phrase derives its name from the sound the roommate makes as he sneaks his way across the room to the bed of his unsuspecting pal.
You shouldn't have slept with my mom, now I'm going to give you The Late-Night Pitter-Patter of your life.
by Spencer Hills 101 September 4, 2009
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