Yet we outlaw murder, rape, etc. Laws don't necessarily stop things from happening. They can be preventive; but, they define what course we take as a society when people act in an unacceptable way. Thus it isn't neccessarily legislating virtue. It's defining how to deal with vice. And society does have a right to reasonable expectations as to individual behavior. Your freedoms end where those of another begin. I see it as my right to defend my family from immorality. Lets say you decide you should be able to sleep with anyone you want to and set eyes on my daughter to charm her into bed. Do I have rights? Does she? Or do you just get to run about impregnating anyone you wish while society foots the bill? Many questions arise very quickly showing it not to be as simple an issue as it may appear - for either side. Unless - you have a moral grounding to begin with. Do you have a right to violate my daughter - no. Do I have a right to stop you from doing it - yes. Should there be a law, maybe. Now take that same issue to a group of atheists. Ask some pornographers.. etc. Ask Gene Simmons for that matter. Opinions vary - right and wrong does not. It will always be wrong to commit murder. To some people, though, Murder is their right..
If she's of legal age? You certainly have the right to try and convince her not to sleep with me. However, if she chooses to sleep with me, you really have no right to prevent us from engaging in the act. In fact, if you threatened me or used violence to stop me, you'd be the one committing an immoral, criminal act.
Does she?
Certainly. She has the right to say no or say yes. If she says no and I force myself onto her, she has the right to defend herself, you have the right to defend her etc. If she says yes, nobody has the right to stop her through force, threats etc.
Do you have a right to violate my daughter - no. Do I have a right to stop you from doing it - yes.
I certainly don't have a right to violate her as my exercising of such "right" would violate her rights to do as she sees fit with her body. Similarly, if she consented to being "violated" as you put it, you would have no right to stop her.