Joey of fiction (3)
I believe the answer is:
roo
'joey of fiction' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for roo that I've seen before include "Diminutive inhabitant of Hundred Acre Wood" , "Kangaroo (Austr. colloq.)" , "large animal" , "bounder" , "Aussie jumper!" .)