Story about non-drinker is gossip (6)
I believe the answer is:
tattle
'is gossip' is the definition.
(I've seen this in another clue)
'story about non-drinker' is the wordplay.
'story' becomes 'tale' (synonyms).
'about' means one lot of letters goes inside another.
'non drinker' becomes 'tt' (abbreviation for teetotaller).
'tale' placed around 'tt' is 'TATTLE'.
(Other definitions for tattle that I've seen before include "Inform on someone" , "'Gossip, idle talk (6)'" , "Chatter idly" , "Tell tales" , "Divulge secrets" .)