1. Collection action: Borrowers usually urge you to repay by phone, text message or email.

2. Increase of interest and late fees: According to the contract, overdue repayment may lead to the accumulation of interest and late fees. This will cost you more.

3. Damaged credit record: Failure to repay debts on time may have a negative impact on your credit record and reduce the credibility of your future application for loans or credit cards.

4. Contacts are harassed: If you provide the information of emergency contacts, they may be harassed by the collection staff to force you to repay the arrears.

5. Legal proceedings: In serious cases, the borrower may take legal measures to recover the arrears, which may lead to further economic and legal problems.

Summary: Failure to return the arrears will lead to collection actions, increase costs, damage credit records, bring trouble to contacts, and may involve legal proceedings. It is suggested to communicate with the borrower in time to solve the problem and avoid further adverse consequences.

Related information: According to Chinese laws, debt may lead to civil litigation and enforcement procedures. The laws and regulations in different regions may be slightly different, please understand them according to the relevant laws in your place.