A more thorough explanation:

Post contractum debitum is a Latin term that refers to a debt that arises after a contract has been made. This type of debt is not included in the original contract but is created due to circumstances that occur after the contract has been signed.

For example, if a person hires a contractor to build a house and the contractor incurs additional expenses due to unforeseen circumstances, the contractor may be entitled to post contractum debitum to cover those expenses.

Another example is if a person rents a car and returns it with damage that was not present at the time of rental. The rental company may charge post contractum debitum to cover the cost of repairing the damage.

These examples illustrate how post contractum debitum can arise due to circumstances that were not anticipated at the time the contract was made. It is important for parties to a contract to be aware of the possibility of post contractum debitum and to include provisions in the contract to address how such debts will be handled.