Once upon a time, there was a village called Diode. The inhabitants were an excitable lot, who tended to get charged easily, positively or negatively.
They liked to play musical chairs. When a negative charge shifted to a higher seat, that was a current of -1. A positive moving down, was also -1.
One day, there were 5 seats, filled with negatives. But Eddie Electron, in #5, had too much sangria at dinner, got sick, and went home, leaving an empty seat, with charge +1, relative to Eddie.
So the other electrons all shifted up one seat, for total current -4. The empty seat shifted down to #1, hence also current of -4. Total current: -8
The next day, Paul Positron, charge +1, occupied seat #5. Again, the negatives all shifted up one seat, total current: -4 Paul moved to #1, for current -4. Thus again, total current: -8
The End