Testicular Torsion

A 9th level spell that can only be casted by the greatest wizards of the realm. When casted, a magical force twists one or both testicles of the persons afflicted, causing immeasurable pain and anguish.

When casted on a person with no junk, the only affects are a mild tummy ache or rampant expulsion of gas from your rectum.

Nice Shopkeeper - "Hello sir, what can I get you today?"
Me, a wizard with a short temper - "TESTICULAR TORSION!!!!"