I think there should be a discussion here about these things. I think there should be a discussion everywhere about these things, but this could be a start.
I think the answer to the problems is that we need to TALK about sexual things. (that includes kissing and touching and all) It's not enough anymore to use the common idea of non verbal consent that exists in our society. No means no, but also anything other than a yes means no too. Even if the less assertive person makes no attempt to stop the assertive one, that's not what matters. What matters is whether they really want it and that can't be decided by body language. It has to be decided by a consistent, continuing, and absolute yes.