Yep Nope

When you think it's safe to fart (YEP) but upon initiating the release (NOPE), you must quickly constrict the sphincter to prevent the flow of shittle from escaping the inter-gluteal cleft and ruining yet another pair of fancy pants.

Dean: Dude, why are you walking like a Penguin?
Jon: I just did a Yep Nope but not sure if I caught it in time...walk close behind me to the nearest bathroom!
Dean: You probably shouldn't have worn those baby blue yoga pants...just sayin'