S.D. Codified Laws § 53-6-2
Current with legislation signed by the governor on or before 3/6/2024
An existing legal obligation resting upon the promiser or a moral obligation originating in some benefit conferred upon the promiser or prejudice suffered by the promisee is also a good consideration for a promise to an extent corresponding with the extent of the obligation, but no further or otherwise.
SDCL 53-6-2