I confess that when I get nervous I get quite gassy. I can't help it.
I remember going over to meet my then-girlfriend's family. I told her I was really, really nervous, and my stomach was churning, and my bowels were rumbling. So she said, "Don't worry, our dog Fido farts a lot. We'll just blame him." I thought it was a plausible plan.
So when we get there, her mother and father and brother and sister all sat in the living room, my girlfriend and me on the couch, and the dog at our feet.
After the customary introductions, the parents start asking me questions, like what I was majoring in at college. The nervousness was getting to me, so a let a tiny fart loose. The father suddenly said, "Fido!"
Ahh, the plan was working!

So as they started asking more questions about my family, I could feel beads of sweat building on my brow. To relieve the tension, I ripped a longer and louder fart. The father reacted with "Fi-do!!"
Safe again.

Then they started asking what my intentions were with their daughter, and the stress was too much, so I really let one rip, shaking the couch as I did. The father jumped to his feet and shouted, "FIDO!!! Get away from that man before he ->-bleeped-<-s on you!!!"
I was never invited back.

Wait?! This isn't the bad joke topic??