One week Sherlock has a cold and of course proceeds to be terribly melodramatic about it, sneezing theatrically here and going into exaggerated coughing fits there and generally making a damned nuisance of himself, in John's opinion.
The next week he is knifed whilst chasing a petty jewellery thief – hardly worth his time – and doesn't even mention it until John notices with an exclamation how white Sherlock has gone and how hard his hand is pressed to the seeping dark stain on his jacket.
In the following months John gets a revenge of sorts by catching the flu, bringing Sherlock to the abrupt and unpleasant realisation that the milk does not replenish itself and that someone needs to stock up on loo rolls every once in a while. Sherlock in a supermarket is not an image that John can readily imagine, although he takes great amusement in doing so, and he tactfully avoids the subject every time the detective returns baleful and exasperated from the shops ("Does that dullard of a cashier honestly not realise that his girlfriend's sleeping with his father? It's blindingly obvious from the state of his shirt collar!").
...Short but sweet? :P
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