Scruff has shag, perhaps, before writing letter ending romance (4)
I believe the answer is:
nape
'scruff' is the definition.
('nape' can be a synonym of 'scruff')
'shag perhaps before writing letter ending romance' is the wordplay.
'shag perhaps' becomes 'nap' (terms for textiles).
'before writing' means one lot of letters go next to another.
'letter ending' says to take the final letters.
The last letter of 'romance' is 'e'.
'nap'+'e'='NAPE'
'has' is the link.
(Other definitions for nape that I've seen before include "It's a pane in the neck" , "Back part of the neck" , "sofa" , "Scrag" , "Scruff of the neck" .)