Popping a cork

This happens after you have been constipated from a piece of stool that backs up your bowels, causing bad enough bloating that you end up getting severe intestinal pain, often in the middle of the night. When that piece finally gets passed, usually after several minutes of straining, groaning, and wincing, everything it was backing up immediately comes out as diarrhea, causing your ass to imitate popping the cork on a bottle of champagne. Ironically, shaking your intestines, whether with your hands or making your legs shake up and down, can assist, in the same way you can shake up champagne to make the cork pop out.