Step-Mommy's doing laundry today in her underwear. After she loads it up and starts the machine, she notices the vibrations as it fills with water and gives her ideas.

She gets on top of the machine and humps it gently for a while, but then she remembers that she stashed a hitachi over here for just such an occasion.

So, she gets it out and makes herself cum with the combined vibration of the machine and the hitachi.

Next time step-mommy does laundry, you should help ;)