When you go on a special diet and don't have a shit for 9 days, then you try and squeeze out a fart that turns out to be a little more than you expected.
Oh my god, she's had a 9 day shit fart.
What follows if you have a 9 Day Shit Fart
Don't have a 9 Day Shit Fart, you'll end up Farting Yourself Into Oblivion