If you don't pay back the money, it will leave a stain on your credit record, and you may be summoned by the police next time you land in Japan. Leaving a stain means that you can't open a bank in Japan, let alone apply for a credit card. If the loan, the possibility is 0.

There is only one way to solve this problem. Pay back the money, and it is best to pay back the money on time. If you can't come to Japan for the time being, you should contact your credit card issuer, tell them the reason and apply for deferred repayment.