A poser's catch? (6)
I believe the answer is:
sitter
This clue is a double definition.
'a poser's' is the first definition.
(I have seen 'A poser' mean 'sitter' so perhaps 'poser' could also mean 'sitter')
'catch?' is the second definition.
(I've seen this before)
(Other definitions for sitter that I've seen before include "Child-minder of sedentary disposition" , "Child minder, sounds sedentary" , "Dolly" , "one rarely missed?" , "Sedentary baby minder?" .)