'you're The Top'

[Khandro]

I'm reading The Letters of Cole Porter & find when he wrote the above, it sparked 'a national game of parodies'. He thought there was none better than one sent to him by Irving Berlin;

You're the burning heat of a bridal suite in use,

You're the breasts of Venus,
You're King Kong's penis,
You're self-abuse.

[Zacs-Master]

Erm.....ok.

[Bazile]

What's the punch line ?