Something that could have been told in a more concise way but is dragged out because the teller doesn't know how to tell a story. It's a play on the annoying clarifier, "Long story short," people use to sum up a digression, which really neverseems to be that short anyway. So instead you say the opposite.
So I was walking into the store the other day, I wanted to get some aspirin because I had thismassiveheadache and I walked down aisle four but they only had Tylenol but that doesn't work and I went to the counter and short story longthis guy was holding up the store!
When my grandmother called me for the 15th time that day to ask how the internet works ("where does it go?") I was feeling such frustragesion that I quickly got off the phone and shouted into my pillow.