Recent sex: cold, messy and unnecessary (10)

I believe the answer is:

excrescent

'unnecessary' is the definition.

'recent sex cold messy' is the wordplay.
'cold' becomes 'c' (eg on taps).
'messy' indicates an anagram.
'recent'+'sex'+'c'='recentsexc'
'recentsexc' anagrammed gives 'EXCRESCENT'.

'and' is the link.

(Another definition for excrescent that I've seen is " Superfluous".)

I've seen this clue in The Guardian.

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