Possible Clues:

• Neck parts supported by travel pillows
• Mane areas
• Barbers trim them
• What shirt tags may irritate
• Spots where mother cats pick up their kittens
• Places where moms grab puppies when they pick them up
• The back sides of necks
• Areas that may be irritated by shirt tags
• Places to pick up kittens?
• Places to pick up cats