Possible Clues:

• High-flier's black dog
• Member of a moneyed social group
• Black dog, one flying all over the place for pleasure
• Wealthy black dog?
• Person mounting semi-precious stone for rich traveller
• Black dog owned by itinerant socialite
• Rich high-flier's black dog
• One racking up the frequent-flier miles
• Frequent traveller using 'The Black Dog'
• Elite flier