It makes one extremely irresistible in fur, somehow (7)
I believe the answer is:
unifier
'it makes one' is the definition.
(something which unifies people or makes them 'one')
'extremely irresistible in fur somehow' is the wordplay.
'extremely' says to hollow out the word (remove centre letters) (only the extremes of the word are used).
'somehow' is an anagram indicator.
'irresistible' with its middle taken out is 'ie'.
'ie'+'in'+'fur'='ieinfur'
'ieinfur' is an anagram of 'UNIFIER'.
(Other definitions for unifier that I've seen before include "Binder" , "One bringing together" , "It makes one" , "Type who joins in" , "One who amalgamates, consolidator" .)