Philanderer giving wife nothing, remains unreliable (9)
I believe the answer is:
womaniser
'philanderer' is the definition.
('womaniser' can be a synonym of 'philanderer')
'wife nothing remains unreliable' is the wordplay.
'wife' becomes 'w'.
'nothing' becomes 'o' (looks like zero - 0).
'unreliable' is an anagram indicator.
'remains' is an anagram of 'maniser'.
'w'+'o'+'maniser'='WOMANISER'
'giving' acts as a link.
(Other definitions for womaniser that I've seen before include "Casanova" , "Lady-killer" , "Philanderer" , "Don Juan" , "Wolf" .)