If you were a cartoon character and had some hysterical fear or paranoia of something what would that 'something' be?
If it were a 'sillier' comic: Fear of Luck, Good or Bad. Anything to do with it. If someone mentions luck, the character would run and scream. Someone pours her a bowl of lucky charms, hysterically screams at the word on the box. Etc.
Children's Birthday Parties. Particulary those one you see yourself being forced to attend too early in the morning.