Its an effing pun. Its also a reference to the saying "once you go black, you'll never go back." If you need to explain anymore obvious jokes, just drop me a PM.
It's a joke on the saying once you go black you'll never go back and pronouncing Che to rhyme with free.
Wait wait, why didn't we all just rush him instead of being forced to make dates with one another? That would have saved us all this time and the pain afterwards.
I usually don't come on down to these parts of the forums, but seeing this topic made me giggle. I have to pick Che simply because that would be one of the most (probably most) interesting 'dates' I'd ever go on.