Antisocial sort troubled big turtle (6-3)

I believe the answer is:

litter-bug

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'antisocial sort' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'troubled big turtle' is the wordplay.
'troubled' indicates anagramming the letters.
'big'+'turtle'='bigturtle'
'bigturtle' anagrammed gives 'LITTER-BUG'.

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I've seen this clue in The Sun.

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