Discworld – Maskerade (Terry Pratchett)

Nanny Ogg had long ago polished off the chops and the beer, but she hadn't got into bed. She lay on it, fully clothed, with her arms behind her head, staring at the dark ceiling.

After a while there was a scratching on the shutters. She got up and opened them.

A huge figure leapt into the room. For a moment the moonlight lit a glistening torso and a mane of black hair. Then the creature dived under the bed.

'Oh, deary deary me,' said Nanny.

She waited for a while, and then fished a chop bone off her tray. There was still a bit of meat on it. She lowered it towards the floor.

A hand shot out and grabbed it.

Nanny sat back.

'Poor little man,' she said.

It was only on the subject of Greebo that Nanny's otherwise keen sense of reality found itself all twisted. To Nanny Ogg he was merely a larger version of the little fluffy kitten he had once been. To everyone else he was a scarred ball of inventive malignancy.

But now he had to deal with a problem seldom encountered by cats. The witches had, a year ago, turned him into a human, for reasons that had seemed quite necessary at the time. It had taken a lot of effort, and his morphogenic field had reasserted itself after a few hours, much to everyone's relief.

But magic is never as simple as people think. It has to obey certain universal laws. And one is that, no matter how hard a thing is to do, once it has been done it'll become a whole lot easier and will therefore be done a lot. A huge mountain might be scaled by strong men only after many centuries of failed attempts, but a few decades later grandmothers will be strolling up it for tea 'and then wandering back afterwards to see where they left their glasses.

In accordance with this law, Greebo's soul had noted that there was one extra option for use in a tight corner (in addition to the usual cat assortment of run, fight, crap or all three together) and that was: Become Human.

It tended to wear off after a short time, most of which he spent searching desperately for a pair of pants.

There were snores from under the bed. Gradually, to Nanny's relief, they turned into a purr.

Then she sat bolt upright. She was some way from the cowshed but…

'He's here,' she said.