Rules for relationships

I had thought, as a guy, that there were certain rules that guys had to follow in order to keep a good relationship going.  Rules that were so crystal clear that they didn't need to be written down.  Hell, rules that are pretty much ingrained in anyone with a functioning brain, in big flashing neon letters that say "DON'T DO THIS OR YOUR RELATIONSHIP IS DONE AND OVER!"

For example, this rule:  You do not ever ever ever EVER stick your dick in a crack whore.

An acquaintance of mine apparently never learned that rule.  It was an interesting night last night.