When you have raunchy anal sex with monkeys and then have the 4 eggspecial in a rundown Dennys in South Central LA. You then go on to buy 19 cherry (NOT Apple) pies and rape them with a thorny dildo. Afterwards you stay up for over 3 weeks watching Avatar the Last Airbender whilst eating sumptuous ammounts of frozen peas.
When you poke someone in their hinder hole when they least expect it. Works best when an individual is under a table. The ensuing reactive jump from the "pooperpoke" should cause the victim to jump and drive their head into the bottom of the table.
I caught Joe under the desk picking up a pencil and I pooperpoked him. He now has a concussion.