Sherlock finds an abandoned litter of kittens in a crawl space during a case, and welp. That case doesn’t get solved because guess who just turned into a cat parent? They get checked out at the vet and then they need bottle feeding for a couple of weeks, and Sherlock gets up dutifully every couple of hours to feed them.
As a condition of this little rescue mission, Sherlock promised to do all the kitten care until the kittens are old enough to be rehomed, but. John can’t sleep without Sherlock anyway, so! John thinks probably he’s never seen anything as wonderful as Sherlock’s face when he’s got a kitten in his elbow and a bottle in his hand.
Anyway, once the kittens are a sprightly twelve weeks old and ready to be adopted, Well three cats really isn’t THAT many, is it, John? And John gripes a little, but he’s sure a hundred cats wouldn’t seem like THAT many if Sherlock asked with that look on his face.