Possible Clues:

• Handlebar or walrus, for example
• Unshaved hair above mouth
• On the face of it, this has to be about nothing with pain
• Facial hair growth
• Hitler's first cat cavorting with mouse under his very nose
• Facial adornment
• Hair on the upper lip
• Let's face it, there's nothing in what has to get sore
• Cat and mouse finally finish grooming whiskers
• Hair growth over parting is bound to itch