Related Clues:

• Bug bomb target
• Buttinsky, e.g.
• Spammer, for one
• Mosquito, e.g.
• Unwelcome visitor
• More than an inconvenience
• Exterminator's quarry
• Constant interrupter
• Persistent annoyer
• Great bother
• Bothersome one
• Major pain
• Bothersome type
• Genuine nuisance
• Telemarketer, perhaps