Once upon a time there was a guy walking along on all fours. He comes to another man who he knows. This man says to the man on all fours, "Mate, what are you doing crawling around on your knees?"
The guy on his knees looks up at him and says, "I'm a turtle, I'm a turtle."
The guy looks at him and goes, "Ahhh, yeah, right-o," and off he went. Next day comes and the same thing happens. The guy asks him again, "Mate, what are you doing crawling around like that?"
"I'm a turtle, I'm a turtle."
The guy goes, "Mate, you've lost your mind, See ya later." Third day, the guy comes around the corner on all fours again, this time he's got a girl on his back. The man says to him, "I thought you'd lost your mind before, but this one really takes the cake. What the hell are you doing now?"
The guy says to him, "I'm a turtle, I'm a turtle."
The other guy goes to him, "But what's that on your back?"
The guy looks up at him and says, "Oh, that's Michelle!"