You do not touch my daughter in front of me. You may glance at her, so long as you do not peer at anything below her neck. If you cannot keep your eyes or hands off of my daughter's body, I will remove them.
I'm sure you've been told that in today's world, sex without utilizing a "barrier method" of some kind can kill you. Let me elaborate: when it comes to sex, I am the barrier, and I will kill you.
Do not lie to me. I may appear to be a pot-bellied, balding, middle-aged, dim-witted has-been. But on issues relating to my daughter, I am the all-knowing, merciless god of your universe. If I ask you where you are going and with whom, you have one chance to tell me the truth, the whole truth and nothing but the truth. I have a shotgun, a shovel, and five acres behind the house. Do not trifle with me.