Here's a tip.
When you get the urge to moon something or someone . . .
Pick your targets carefully.
Utrecht police say a 21-year-old Dutch man is recovering after a "mooning" that went horribly wrong.
A police statement says the man and two others had run down a street in Utrecht with their pants pulled down in the back "for a joke".
It says that at one point the 21-year-old "pushed his behind against the window of a restaurant" that broke and resulted in "deep wounds to his derriere".
The statement says police detained the three men after the incident Sunday morning. But the cafe owner decided not to press charges after the men agreed to pay for the broken window.
The injured man was treated for his injuries at a nearby hospital.