A John is a sexy beast with an amazing sense of humor. He's smart, a bit geeky, and an awesome guy to be around. A John without pants is automatically a win in every situation.
"I wish I were a John." "John is the coolest guy ever."
"Whoa! Look at that sexy model!" ... "No way, man, that John has his pants off! Win."
"Hey look, I just ran a marathon!" ... "You know what's even better? That pants-less John over there."