A more thorough explanation:

societas leonina

Societas leonina is a type of illegal partnership in Roman law where one partner only shares in the losses and not the profits. It is like a partnership where one person takes the lion's share.

An example of societas leonina is when two people start a business together, but one person only invests money and does not contribute to the work. If the business makes a profit, the person who invested money takes all the profit, but if the business loses money, both partners share the loss equally.

Another example is when a group of friends go on a trip together, but one person pays for everything and expects the others to pay them back later. If the trip ends up being expensive, everyone shares the cost equally, but if the trip is cheap, the person who paid for everything takes all the savings.

These examples illustrate societas leonina because in both cases, one person is taking all the benefits while the other person or people are only sharing in the losses. This is not fair or legal in a true partnership where all parties should share in both the profits and losses equally.