December 4: "Holmes unwittingly ruins everything." (from Temporarily Abaft)
A/N: Written in third person.
"Sherlock! Do you have any idea how serious this is?!" Mycroft glared at his brother from across his desk, grey eyes blazing.
"I had no idea the man was a Russian diplomat, Mycroft!" Sherlock threw his arms in the air. "Tell me, how was I to know?!"
"Maybe you could've use your bloody God-given brains to see that what you said was horribly offensive—whether it was to a diplomat or anybody else! You've ruined the Christmas party for everyone, and may well have started a war!" The elder Holmes slammed a fist down on his table in frustration.
Sherlock took a deep breath and slowly exhaled through his nose, trying to keep his temper in check. "Mycroft, do calm down. I am sure you will sort it all out."
"As per usual, I am left to clean up the mess you leave behind!" Mycroft sighed and pinched the bridge of his nose. "Get out of my office, I have a good deal of work ahead of me."