Related Clues:

• Sitting challenge
• Bug you want to swat
• Source of exasperation
• Irritating sort
• Little cut-up
• Aphid, to a fruit tree
• Dennis the Menace, to Mr. Wilson
• Mini-demon
• Little mischief maker
• Quite a handful
• Mosquito or mole, e.g.
• Fly, perhaps
• 17-Across in the neck
• Picayune prankster
• Annoying bug