More torture

As the vacuum starts to suck, she slides you down the bench slightly so that your butt and crotch are hanging off the end, while the rest of your body including your hands are tied securely around the bench, holding you in place.

She pulls what looks like a miniature floor buffer out of her bag. It's designed to rotate the end around in a vibrating motion that really grinds into the floor.

She yanks the head off of it, so it's just a small metal rod that comes to a rounded end.

She flips it on and sees it rotate around while shaking. She has an approving look on her face.

She starts sliding her fingers over your ass, making you jump at the touch.

She grabs a gob of jelly and slathers it over the vibrating metal rod.
Then, she slowly eases it into you.

You wince in pain and try to struggle. She's loving it. Every ounce you squirm makes her laugh.