Let's say you are on a date.
He's a funny fella and you begin to laugh rather vigorously in the ice cream aisle.
Let's say you then have a sneak attack of gaseous emissions.
You can see him trying to remain composed.
Let's say you then begin to laugh uncontrollably instead of succumbing to the embarrassment.
You are both then laughing like hyenas in the ice cream aisle, scaring away any passersby.
Let's say you are me and it was last Saturday night. Now aren't you glad it wasn't you?