Mycroft Holmes, known to his brother as a Fat Figure in the British Government, or Fatty, for short, was strolling through London one day, twirling his umbrella, and humming proudly to himself. He had made up a little hum that very morning, as he was doing his Stoutness Exercises in front of the glass: Tra-la-la, tra-la-la, as he stretched up as high as he could go, and then Tra-la-la, tra-la — oh, help! — la, as he tried to reach his toes. Well, he was humming this hum to himself, and walking along gaily, when he noticed he was in front of New Scotland Yard.

"Aha!" said Mycroft. "If I know anything about anything," he said, "New Scotland Yard means D.I. Lestrade," he said, "and Lestrade means Company, and Listening-to-Me-Humming, and Doughnuts, and such like. I think I shall pop in."

When he reached the D.I.'s office, Mycroft found that Lestrade was out, but the doughnuts, fortunately, were in, so Mycroft went in likewise, and made himself at home. He had just bitten into a luscious doughnut with rainbow sprinkles when he heard a most unwelcome sound: Sherlock and John, talking and laughing and heading his way.

"Oh, bother!" said Mycroft. "My brother is sure to poke fun at me for indulging in this doughnut. I wonder if I can avoid him?"

Looking around, Mycroft spotted a gym bag in one corner. It was quite a large gym bag: large enough to fit a man — even a man who indulged in the occasional doughnut. Mycroft found, on climbing into the bag, that there was even a bit of extra room inside — just the right amount of extra room to fit a box of doughnuts. So Mycroft brought the box of doughnuts in with him.

No sooner had Mycroft hidden himself and the box of doughnuts in the gym bag than Sherlock and John knocked on Lestrade's office door. Mycroft stayed silent, and hoped they would go away.

"Lestrade? Are you in?" called John.

Mycroft had no intention of answering, but even had he wanted to, it would have been difficult, as his mouth was currently employed in eating a glazed doughnut.

Sherlock, who never waited on an invitation before entering a room, opened the door and came into the office, with John in his wake. Mycroft could hear the two of them walking over to Lestrade's desk. He kept perfectly still, except for his mouth, which was now full of Boston Crème.

"There's no one here," said John. "We should come back later."

"There is someone here," said Sherlock. "I smell doughnuts, and I can hear someone chewing."

"I think there's someone in that gym bag," said John.

"Kick it and find out," said Sherlock.

"No!" said Mycroft, although his voice was muffled by the gym bag, as well as by the vanilla frosted doughnut in his mouth.

"Is that Mycroft?" asked John.

"No," said Mycroft, in a different sort of voice this time.

"But isn't that Mycroft's voice?"

"No," said Mycroft. "At least, it isn't meant to be."

"Oh, this is rich!" said Sherlock. "Fatty-Fatty-Fatcroft, who's never been to a gym in his life, is hiding in a gym bag, eating doughnuts. You'll have to write this one up on your blog, John. I'm sure you'll think of a clever title. Don't Let the Fat Out of the Bag, perhaps."

"Ha ha," said Mycroft sourly, although his lips still tasted sweet from the icing sugar clinging to them.

Just then Lestrade returned to his office. "What's going on?" he asked.

"I think you need a new gym bag," said Sherlock. "There's something nasty stuck in your old one."

"I am not stuck," said Mycroft, although he was, in fact, having a bit of difficulty in extricating himself from the gym bag.

"Do you need a hand?" asked Lestrade, crossing the room and helping to loosen the laces that were cinching the bag shut. "How did you manage to get yourself stuck in here, anyway?"

"It all comes," said Mycroft crossly, "of not having bags with big enough openings."

"It all comes," said Sherlock gleefully, "of eating too much. You devoured an entire box of doughnuts while you were in that bag, and now you're too fat to get out."

"I did not eat them all," said Mycroft. "I saved the last one for Lestrade."

"Next time, maybe you shouldn't eat any doughnuts at all, if you're going to be getting into such a tight place," said John.

"I know a tight place I wouldn't mind getting into," said Lestrade.

Mycroft flushed, John smirked, and Sherlock fled the scene with his hands over his ears.

Lestrade reached for the last doughnut. "Mmm… Double caramel… Delicious… There's only one thing I'd rather have in my mouth…"

"Help me get out of this bag," said Mycroft, "and then we can indulge your mouth and my tight place to our hearts' content."

The End

End Note: This story is based on A.A. Milne's Winnie-the-Pooh, and written in response to may-shepard's tumblr prompt:
1. Put Sherlock in a gym bag, in a fic.
ALTERNATIVELY
2. Put John in a gym bag.
OR
3. I mean just fucking put someone in a gym bag.

Clearly, I went with option 3 here. If you'd like to read my response to option 1, check out "Got to Get You Out of This Bag." :D