Next, step back a few steps, then hold your ground. DO NOT turn away. STARE HIM DOWN. Make him retreat.
If he doesn't leave continue making a commotion. Let everyone know he's a creep.
After the confrontation, go about the store for awhile. 10-15 minutes or longer. Do your shopping. Calm yourself down
When leaving keep your senses ALERT.
I use brute force when anybody gets in between me and my daughter for what ever reasons, especially with that scenario.
You have one warning, you ignore it, you will eat dirt, pronto. Want to be a wise guy, it is up to you...
and your 40 S&W handy.