illegal lending; loan sharking; black-market loan
Refers to unregistered, high-interest lending outside legal regulations; often associated with yakuza or underground operations.
闇金融から借りると、法外な利息を取られる。
If you borrow from an illegal lender, you'll be charged exorbitant interest.
警察はヤミ金融の取り締まりを強化している。
The police are cracking down on illegal lending operations.