Some of Bill Maher's rules are easier to follow than others. This one should be a no-brainer.
But no one makes a rule unless it's already been broken by at least one person (or in this case one couple) so while this may seem like a given to most of us, clearly, it was a bit of a gray area for others.
Remember, your sex life is your business, but when you involve Craigslist -- and animals -- you're just inviting all kinds of scrutiny.
"Real Time" airs Fridays at 10:00 p.m. on HBO.