The mixture of steam, typically from a running shower, with the odors of fresh sewage to produce a thick gas powerful enough to trigger an asthma attack.
After Larry got back from Taco Bell, he took a shit so massive that he had to take a shower afterwards. However, he forgot to flush, and the smell mixed with the steam producing a poop smog that lingered for three days.
The Poop Exchange is a method where you sit on top of someone, assholes face to face, and then you shit down the other persons asshole. Once you’re finished the other person sucks up the poop up into their rectum and absorbs all the shits nutrients.