You keep at it

You try to keep at it, but going onward feels ever more difficult. You move a couple steps, then you stop. Then you move a couple steps, and you stop again, all the while Master yells at you to increase your pace.

You teeth gritting on the gag, you try keeping at it, but all you manage to do is small patches, you standing still each time an orgasm nears.

With the half an hour coming to a close, Master unlocks you from the device “We will have to rehearse this tomorrow.”, and you are escorted back to the living room, strapped to your previous position.

You proceed to kneel in your stance idle, and you keep at it until the night when Master and Mistress lie down in the bed and start watching holo-tv. Out of a sudden, he starts pressing on your left breast. And the game begins.