Rub her pussy through her pantyhose

You stick your hand between her legs and caress her pussy through the crotch panel of her shiny hose. She puts the glass down carefully so as to not break it and moans softly to her surprise. This was not something she wanted, but her body was reacting to the stimulation and she couldn't deny that

"Brandon, please, it isn't right for you to touch your mother there!" she says.

Your penis is stiff as a board inside your pants as you hear her trying so hard to supress any further moans. You want her to let them all out, to let you know that she was enjoying this. But since just rubbing her wasn't enough, you would have to get a bit rougher if you were going to be able to break her like you wanted.