You lend a user ₦100,000 for one month at 5% interest (₦5,000). Three ledger events: the disbursement, the interest accrual, and the repayment. The principal flows OUT of your bank into a loan receivable on your books, it's still your money, just lent. The interest accrues against the user separately. Each payment clears principal AND interest in one entry. Get the lifecycle right and you can build any lending product. Get it wrong and your loan book numbers lie.