Adult works at aerobics, desperately wanting shaped abs (7)
I believe the answer is:
erotica
'adult' is the definition.
Both the answer and definition are singular nouns.
Maybe there's a link between them I don't understand?
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for erotica that I've seen before include "Sexually stimulating literature" , "literature of a sort" , "Amorous literature" , "pornography" , "Objects designed to arouse sexual desire" .)