Fun, sin and faults he elaborated – adultery? (14)

I believe the answer is:

unfaithfulness

'adultery?' is the definition.
(adultery is being unfaithful to a partner)

'fun sin and faults he elaborated' is the wordplay.
'and' is a charade indicator (letters next to each other).
'elaborated' indicates an anagram (an elaborate version of the letters).
'fun'+'sin'+'faults'+'he'='funsinfaultshe'
'funsinfaultshe' anagrammed gives 'UNFAITHFULNESS'.

I've seen this clue in The Independent.

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