Loving a coffee — 'taint unusual (12)
I believe the answer is:
affectionate
'loving' is the definition.
('affectionate' can be similar in meaning to 'loving')
'a coffee 'taint unusual' is the wordplay.
'unusual' indicates an anagram.
'coffee'+'taint'='coffeetaint'
'coffeetaint' anagrammed gives 'ffectionate'.
'a'+'ffectionate'='AFFECTIONATE'
(Other definitions for affectionate that I've seen before include "Expressing fondness" , "Displaying fondness" , "Tender" , "Warm-hearted - loving" , "friendly" .)