When will you do this? For how long?

Consent in a scene is finite with a specific start and end time.  It is important to agree on what those will be, especially if you have agreed that the Top is permitted to force the bottom to do things or have elements of non-con (consensual non-consent) to the scene.

Make it clear to your partner that it is okay for them to back out of any activity at any time for any reason. Reminding each person of this fact can be critically important to creating an emotionally safe environment.