The wolf and the bei are two beasts that look and act alike, but with a key difference: the wolf has long front legs and short hind legs, while the bei has short front legs and long hind legs. They often team up to raid livestock, causing great harm to humans.
One day, a wolf and a jackal crept up to a farmer's sheep pen, knowing it was full of sheep and hoping to steal one for a meal. But the pen was built high and strong—too high to jump over, too solid to break through—and for a moment, they had no idea what to do.
After some deliberation, they devised a plan: the wolf would ride on the wolf-dog's neck, while the wolf-dog stood on its long hind legs, hoisting the wolf high. Then, using its long front paws, the wolf would grip the sheep pen and snatch the sheep away.
In this operation, if only the wolf or only the wolf-like creature had acted alone, neither could have climbed into the sheepfold to steal the sheep; however, by leveraging each other's strengths and working together, they managed to pull off the theft.
Later, people derived the idiom "colluding like wolves" from this story, using it to describe two or more people banding together to do evil deeds.
Source: *Bowu Dianhui*
Meaning of the Idiom: Later, the Chinese idiom "狼狈为奸" came to describe two or more people banding together to do evil deeds.