Quite creepy. Lots of cyclists on the road here, and once in a while I end up drafting off someone, or the other way around. Don't mind the chat. However I've had one creepy event (just a gut feeling) and told the guy I didn't want anyone drafting off me.

I suggest doing the same thing, telling the guy to either drop back or pass you, you're not wanting anyone on your wheel.

There's always snot rockets, also.

I like to imagine that a guy with bad intentions wouldn't find a likely victim in a woman who performs good snot rockets... !!!