2.1.53 पापाणके कुत्सितैः

The words पाप and अणक with कुत्सन-indicating सुबन्त have तत्पुरुष status (unlike what is dictated in 2.1.52). For example, पापश्च असौ नापितश्च - पापनापितः i.e. समास results.