Being a "Big Joe" Is when a male happens to have an absolutely massive penis, like, ridiculously huge- A Cock big enough to balance a horse on, when it isn't erect. These guys can snap cars in half with one mighty swing.
Their motto tends to be "If it exists, my dick can break it."
When they get erections, only a wormhole could fit the bastards.
Detective - "So far, we have established that the woman was torn in half down the middle, possibly by the insertion of an object into her vagina, which was so big she tore in two."
Detective 2 - "Must have been a Big Joe."