The painful but somewhat stimulating anal sensation you experience the morning after eating too many of the hottest buffalo wings the bar offers (e.g., BWW's Blazers). Some Indian food can have the same effect but usually it is only from some very irresponsible sadistic joker.
Steve: "Try these wings, they burn more coming out than going in."
Joe: "meh, they're not so bad but I can tell from the smell that they prolly are morning afterburners."
1: The overwhelming sense of pain experienced shortly after the initial injury is inflicted.
2: A Phrase spoken by someone who is experiencing the feelings described in definition 1.
(John) "Kidney punch!!!"
(Mike)"Ouch that kinda hurt... (Waits for a second) Holy shit balls, AFTERHURT!!! (Rolls on floor making hissing sounds and incoherent strings of profanities whilst Mike laughs hysterically.)