Once, a fox and a hare became friends to defend themselves against their joint enemy, the hunters. They swore an oath to share life and death, through thick and thin.
One day, while enjoying the beauty of the fields, a group of hunters arrived and shot the hare dead. The fox narrowly escaped. After the hunters left, the fox returned and wept over his friend's body.
An elderly gentleman passing by was surprised by the scene. Curiously, he asked the fox why she was weeping so bitterly.
The fox replied sorrowfully: "We are small animals, the prey of hunters. We pledged to stand together against our common enemy, sharing life and death. Now, my companion has been killed. His death today may mean mine tomorrow. We are true friends. How could I not weep?"
"Oh, I see," exclaimed the gentleman. "You have good reason to mourn such a partner."
The idiom "The fox is sad at the death of the hare" originates from this story, illustrating the feeling of sorrow one has for the death or misfortune of a companion.