Helpless victim modelling with nothing on (7,4)
I believe the answer is:
sitting duck
'helpless victim' is the definition.
(I've seen this before)
'modelling with nothing on' is the wordplay.
'modelling with' becomes 'sitting' ('sit' can be a synonym of 'model'. I am not sure about the 'with' bit.).
'nothing' becomes 'duck' (duck means zero in cricket).
'on' says to put letters next to each other.
'sitting'+'duck'='SITTING DUCK'
Can you help me to learn more?
(Other definitions for sitting duck that I've seen before include "Unmissable target" , "Potential victim" , "Obvious target" , "Wide-open target" , "Easy target" .)