Before the invention of Banks, there were wealthy people like Subuola whose sole business is to lend people money with interest in return. When people want to lend money, they make promises but when it is time to return the money lent, they ask for mercy. This shows that people borrow money for frivolous reasons like burial ceremony, weddings etc and not for business investment. These debtors would run Subuola out of business but in trying to protect her own interest, she runs into trouble which is against the law.
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