Related Clues:

• Arouse 16-Down
• Words on a diner ad, perhaps
• Heat up
• Stir (up)
• Really get to
• Make upset
• Get on one's nerves
• Make furious
• Obsess
• Raise one's hackles
• Provoke to anger
• Really worry
• Rouse to anger
• Bug and then some
• Vex a lot