Sure. Agreeing to sex and then regretting it is not the same as rape.
Your example, however, is rape. The minute consent is withdrawn, sex ends or it becomes rape. I would never do that to a guy. And that's happened. I've been with a guy who wanted to stop because he got too tired and was sore so I stopped. If I hadn't, that would have been rape. Should the sentence be the same? Nah. But there needs to be some kind of punishment because I would have taken away someone's bodily autonomy. And that's wrong.
We all need to be secure in our persons. It's a fundamental human right. Without that basic respect between persons any society will inevitably fall intoxicated acts of atrocity. It is the reason why we exploit each other. We don't embrace and fight for the security of personhood for everyone.