Awkwardness ensues.
Hidden Hurt
"O-Oh," said the customer in surprise, glancing over his shoulder at John. "Sorry about that..."
John quickly shook his head. "Ah, no, it's fine," he said quickly.
Sherlock began to walk forward. "John, the umbrella-"
"You two really do know each other then?" The suited customer seemed intrigued.
"Yes," said Sherlock. "John's my friend."
"Colleague," said John suddenly, turning back to finish off the drinks.
He didn't notice the flash of surprise that quickly turned to melancholy in Sherlock's blue-green eyes, nor the minute stumble in his words. "Yes. Quite right."
"Wonderful to meet you, John. I'm Jim!"
Prompt was #59: blue-green
To all those who guessed Jim, you're quite right.
Inspired by the fleeting disturbed look on Sherlock's face in "The Blind Banker" when John corrected his terming of their relationship.