When you are trying to poo (shit) but the faeces gets lodged in the opening to the anal cavity, often known as a turtle's headpoking out. When you can push no more, but the turtle remains trapped, wiping during this scenario is known as Wiping the Turtle's mouth.
Craig came back from the dunger and informed Jon "That was a tough one Jon, I just ended up wiping the turtle's mouth" Jon understoodinstantly.
Bill: "Hey Steve. I did a huge dump this morning which was so perfect that I almost had a orgasm"
Steve: "ah, I see you have experienced the majesty of The Turtle's Kiss"
Adverb, Metaphor - Describes a crisis of chronic defecation.
Example
Whist the turtle's head (turd) is about to fully emerge from its shell, there happens upon it a sudden and quite shocking movement of the bowel.
Because the body believes that such a surge of power must surely occur DURING the ejection of the faeces, (even though the victim is retaining the load) the sphincter begins to air-spasm as if snapping the enormous delivery into manageable chunks. The resulting involuntary bodily event is euphemistically known as 'A Snapping Turtle's Head.
It was when I was a minute from my station and too late to escape using the toilet on the train, yet knowing that there WAS a toilet at the approaching platform, that the situation turned critical, the danger imminent! Although I had retained a calm control over the crisis I could only resign myself to the cradle of fate when my body went into SNAPPING TURTLE'S HEAD !