Related Clues:

• Tick, e.g.
• Little brother or spammer, to some
• Gnat or rat
• Irksome fellow
• Starling, e.g.
• Slug, to a gardener
• Pain of a sort
• Pain in the rear
• Mixed-up PETS?
• Auger or drill
• Orkin victim
• Kibitzer, e.g.
• Gnat, for one
• Kid brother, stereotypically
• Unwelcome greenhouse guest