Animal used to describe the breath of a person when that person's breath is so foul that no other living animal can compare.
This persons breath smells like the ass of such a horrible being that there is no conceivable animal on Earth to compare it to. Therefore, an independent counsel was formed consisting of top scientists from the animal wildlife federation and higher-ups from the dental hygienists association to come up with a new animal that could be a on par with the foul nature of this person's breath. This animal they called the “Shitopotamus.”
“…Charlie’s breath smells like a Shitopotamus.”
A bowel movement so large that it gets wedged at the bottom of the toilet bowl and peeks out above the water.
After not pooing for days, John released a Shitopotamus so large that the ASPCA deployed their emergency animal rescue squad.