So yeah, I can imagine myself giving a clear "yes" to something in that state despite being consciously unaware of the entire thing. I'm not sure if "approval" like that should count court - I'm just giving you an example of one possible complication for "determining whether someone is conscious", be it before sex or otherwise.
Right...
No, it doesn't.
I know someone that was raped while not being conscious. She didn't want to have sex with that person. While trying to press charge, she found others persons that had similar experience with that guy. The cops told her tough luck, not to stay with people she didn't trust (it was a friend...) and they threaten her of making false accusation (the prosecutor herself seemed surprised of that and the cops angrily answered that she wouldn't be accused of that, luckily). The prosecutor has not enough proof to go further with it... there should have been at least someone else in that room that could testify.
That's the current state of rape accusation. Pretty far from your "kissing of a sleeping lover" being criminalized.