俱舍論記 15.148

15.148

「樂是此業異熟果故」者，答。由業感樂，樂果起時果領樂因，故名能受。

Regarding "Because pleasure is the fruitional result of this karma," this is an answer. Because karma brings about pleasure, when the pleasant result arises, the result receives the pleasant cause; hence it is called 'capable of experiencing.'