Affected material finally deleted (4)

I believe the answer is:

twee

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'affected' is the definition.
(I've seen this before)

I don't understand how the rest of the clue works.

(Other definitions for twee that I've seen before include "Sickly sweet" , "Sentimentally sweet" , "Mawkish" , "Rather too pretty" , "Overly precious" .)

I've seen this clue in The Independent and The Sun.

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