One who wrote nonsense about the kid, perhaps (7)
I believe the answer is:
Here is my best explanation:
This clue might be a double definition.
'one who wrote nonsense' is the first definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
'the kid perhaps' is the second definition.
(kid is a kind of leather)
'about' is the link.
(Other definitions for leather that I've seen before include "Morocco, perhaps", "Tanned animal skin", "Dressed hide", "kid, say", "Thrash", "Treated animal skin", "Whip", "durable material", "Animal hide" and "Tanned animal hide".)