I was trying to picture this, but couldn't figure how you'd look them in the eye while biting their ear. Maybe some ears badly stretched from wearing huge guages? Or they resemble the guy kept in the basement in "Goonies"?
I find a very firm grasp of their throat, while standing on their foot and looking them firmly in the eye while biting their ear at the same time as hissing 'NO' in it works.
Seriously though telling someone it's inappropriate isn't enough, you have to tell them if they touch you again you will arrest them for assault and you will drag their limp body into the police station to charge them......okay that's just me.
