You've always thought of Hyenas as being rather comical creatures so you decide to visit the Hyena Den.
When you get there you find yourself the only one there. Looking in the enclosure you only see one Hyena, slumped in a corner. "Hey!" you call, pressing your self against the bars "You're supposed to be a LAUGHING hyena! Lighten up!"
The hyena instantly gets up, goes up to you and reaches through the bars with its paw - but instead of swiping you it actually starts tickling your tummy!
"Hee hee hee!" you giggle as you are forced to back away. "You're supposed to be laughing, not me!"
"Oh I'll be laughing all right soon enough!" replies the Hyena with a wicked grin "I've put a curse on you. Every time you laugh from now on, you'll turn into a werehyena. You'll only turn back when you cry.!"