You could tie a rope diagonally across your room, maybe if you have two doors you could use the handles, if you have some heavy chairs, whatever you can fix them too that won't move. This rope will need to be pulled taut so that your submissive needs to be up on her tiptoes with it between her legs, and have multiple large knots tied along its length.
Your submissive starts at one side of the room, straddling the tightrope so it's tight in her pussy. You could start her in high heels and then take one off when she's so far along, the other one at the two-third or three-quarter point. And she's either cuffed or tied, the keys to her release at the opposite side of the rope.
This forces her to have to hobble across the tightrope, forcing herself to slide her intimate parts across the rope. The longer it is and the more knots she has to force herself across, the more of an ordeal it becomes.
Or you could bind her between two fixed points and tie her breasts to something in front of her, and a crotchrope tied to something behind her. You can sacrifice either binding for clamps on her nipples or labia (obviously the clover style clamps will work best) and then you'll want to pull the rope pulling one of them really taut, with a little bit of slack in the other.
Now she can move slightly forwards or backwards, easing the pressure on one part of her but increasing it on the other.