Here's a routine that I've come up with and field-tested a few times, with positive results:
Basically you want to find a good self-defense technique. Here's some links:
http://beauty.expertvillage.com/intervi ... efense.htm,
http://www.youtube.com/watch?v=vEtzFLWdE-k.
But, you may want to google wrist-grab or something of the sort. Essentially the best self-defense technique for this would be something that will allow you not to hurt her, and has a lot of kino opportunity. Make sure you know the self-defense technique well enough that you can teach another person. Try it on your friends, and then try teaching them.
With the technique leant you can build a very strong routine around it. Since I'm a martial artist the way I usually go about is like this:
Newton: What do you do for fun?
HB: blah blah work out blah blah
Newton: Awesome?! You work out? I'm actually addicted to working out. Yeah, I'm a martial artist. (Go into my story about starting martial arts, what I like about it, what I've learned.)
Newton: Hey, let me show you a self-defense technique just incase some guy gets too fresh and I'm not around.
From there you have good kino, not to mention all the DHV. It's also very easy to banter along, like pretend that she hurt you seriously after you have her perform it on you, or tell her she has huge muscles or something.
It's very flexible and can be used in many different stages of your interaction. Of course, you're probably not a martial artist, but it should still fit along. Just say something silly like: "I saw this kick ass move in a Bruce Lee movie," or "You're going to be my bodyguard for tonight, but let me show you something." Just use your imagination.