[garder80]

"Semi public spanking"

Dress in a miniskirt, no panties, high heels and a top that shows cleavage
Wear the but-plug with toothpaste on.
Go to a public bathroom
Find a free stall - don't lock the door. (you have to hold the door with your hand)
edge yourself
bring a hairbrush and spank yourself hard 30 times on each cheek this time saying "I'm a naughty brat" (5 seconds between each spank)
Of someone enters the area you may stop the spanking, and masturbate instead while they are in there (don't cum). Resume the spanking after they are gone.

after the spanking: edge 3 times or until you have pussy juice running down your legs, feel free to insert fingers and rub some juice on the legs as well.

on your walk home, you will lift your skirt to show your ass every time you pass someone. (thus giving them a glimpse of your red ass if they turn around. )

extreme edition1: Do the spanking naked
and/or
extreme edition2: do the spanking outside the stall (in the area with the sinks and blow dryers)
and then run inside the stall if someone enters.