Possible Clues:

• Non-contact sign of affection
• Distant sign of affection?
• Affectation involving almost entirely missing cheek, is this
• Romantic gesture from across the room, perhaps
• Simulated affection is a risk to doctor
• (Mwah!)
• A risk is diverted with this greeting?
• Action accompanied by a 'Mwah!'
• Greeting with a 'mwah' sound
• Touchless greeting