It's fine after love in New York (5)
I believe the answer is:
nooky
'it's' is the definition.
I can't tell whether this definition defines the answer.
'fine after love in new york' is the wordplay.
'fine' becomes 'ok' (synonyms).
'after' means one lot of letters go next to another.
'love' becomes 'o' (In tennis, 'love' means 'zero').
'in' is an insertion indicator.
'new york' becomes 'ny'.
'ok' put after 'o' is 'ook'.
'ook' placed within 'ny' is 'NOOKY'.
(Other definitions for nooky that I've seen before include "Congress" , "Sexual activity (slang)" .)