When a man and woman are
having sex 'doggie-style', with the man wearting a condom, and the man says,
"Oh look, a disappearing panda."
And
when the woman turns to look at the man, he
quickly pulls out, removes the condom and snaps her in the eye with it.
As in the previous example, which did not state the sex being
engaged in was 'doggie-style',
"I can't believe how dumb she is. I
actually pulled a Disappearing Panda on her
last night."