Very similar to the Asian Thunderstorm. When a guy cums on a girls face and then goes lay a fart in her mouth, but instead shits in her mouth.
While eating hot wings and drinking cheap beer, Janet was begging me to give her an Asian Thunderstorm. Later that night I did, but she wound up with a Guatemalan Mudslide instead.
The act of having sex, while releasing ones bolus
Josh was having a dump while his girlfriend was riding him, thus Josh gave his girlfriend a Guatemalan Mudslide