There was a sparrow who lived with a cat as his companion. The two of them played together, the sparrow poking the cat with his beak, and the cat gently swatting the bird with his paw.
Then another sparrow came to live with them, but she was not a nice bird at all. She attacked the cat and she attacked the cat's sparrow-friend too.
"This is unacceptable!" exclaimed the cat. He killed the wicked sparrow and ate her.
"Delicious!" said the cat. "I had no idea that sparrows were so good to eat!"
He then devoured his sparrow-friend as well.
Inspired by: Mille Fabulae et Una, a collection of Latin fables that I've edited, free to read online. I am not translating the Latin here; instead, I am just telling a 100-word version of the fable.
Notes: This is fable 393 in the book, which is not in Perry's catalog; the story is from La Fontaine.