since you are co-borrower then you have to settle or re-pay jointly otherwise bank can auction the secured property.
CIBIL is an Autonomous Body whose full form is (Credit Information Bureau (India) Limited.). The Credit Score is gaining importance as any person having any kind of loan (Personal Loan, Home Loan, Car Loan, Two Wheeler Loan, Business Loan etc) or credit card or Overdraft Limit or even Inquiries with Financial Institutions for taking loan or even acting as guarantor or co-applicant.
CIBIL score signifies that how well have you repaid your previous loans and credit card obligations in the past basis which you get a score. CIBIL match signifies your repayment pattern - i.e how many loans have you taken from what time period of opening to close.