Myself
Who was the worst person you ever met?

I bought a Slurpee at a gas station, and it was $3.07. I handed her 3 $1 bills, and said that that was all I had.
She didn't let me buy the Slurpee. Until I magically found another dollar in my pocket and she gave me mostly pennies in change.
You don't have to say their real name, just what they did.