S.C. Code Ann. § 37-3-405: Charges as a result of default prohibited except as authorized by title.

Except for reasonable expenses incurred in realizing on a security interest, the agreement with respect to a consumer loan may not provide for charges as a result of default by the debtor other than those authorized by this title. A provision in violation of this section is unenforceable. This section does not prohibit or limit delinquency or deferral charges.