Methane and sulfur compounds are stuff that comes out of your butt. It's basically a fart. The methane is the loud part of the fart, while the sulfur compounds are the stinky part. The more sulfur compounds it has, the stinkier the fart.
An extremely stinky bathroom- one that smells like an overflowing septic tank is right underneath it. Meth labs generally have several stalls, each of which is equally noxious.
When a man is performing oral sex on a red headed woman with a fully developedred bush, just as the woman begins to reach climax she squeezes out a gas whisper in her partners face.
A man with long, greasy hair, green teeth, baggy pinstripe trousers with braces and white plimmies. He sneaks around on farmland waiting for a cow to drop a pat. Slavering with excitement he drops his pants and swivels his bare arse on the still-warm bovine pancake whilst making high-pitched mooing sounds.