If this is true, what were they?

Yes there are lyrics and here they are:

No matter where they go
They are known as the couple.
They're never seen alone
So they're known as the couple.

As I've indicated
They are never quite separated,
They are peas in a pod.
Don't you think that it's odd.

Their habits, I confess
None can guess with the couple.
If one says no it's yes
more or less, with the couple.

But they're laugh provoking;
Yet they really don't know they're joking.
Don't you find
When love is blind
It's kind of odd.

You can hear it here. http://www.youtube.com/watch?v=Syt8qQUbzVc
First it plays without lyrics. Then it plays with the lyrics.

I was not aware of this- interesting. Thanks for posting. :) It's one of my favorite TV themes.