Female depressed about habitual seducer (4)
I believe the answer is:
'habitual seducer' is the definition.
(wolf can mean a seductive person)
'female depressed about' is the wordplay.
'female' becomes 'f' (abbreviation).
'depressed' becomes 'low' (synonyms).
'about' shows that the letters should be reversed in order.
'flow' backwards is 'WOLF'.
(Other definitions for wolf that I've seen before include "character of Prokofiev's music" , "Carnivore -- breed of 13 down" , "Pack-hunting animal" , "Predator that hunts in packs" , "SECOND PART OF 14" .)