Alias Public -> Public Sex

Reason: According to the wiki, these tags have the same meaning.

(It might be better to change the meaning of public to just the safe meaning of it, implicate all the public_sex images to public, and then make a tagging project to clean up the loose ends. That's more work, of course.)

You can be out in public without having sex in public. I think your second option (though more work) is a better and clearer choice.