Its entertaining. It uses an unlikely or improbable situation. It may involve disguise or mistaken identity. The potential for verbal humour including sexual innuendo and wordplay is enormous. The speed of the plot should increased to an endpoint involving an elaborate chase and unlikely outcome.
Its farce. And Banksy's image provides everything you need to know. Just enough naughtyness. Just that perfect moment representing all those wonderful moments in British farce.
And then there's the perfect positioning of hands. Left of course.