A secretive person wearing pig-tail getting seafood (9)

I believe the answer is:

oystering

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'a secretive person wearing pig-tail getting seafood' is the definition.
I can't tell whether this definition defines the answer.

'a secretive person wearing pig-tail' is the wordplay.
'a secretive person' becomes 'oyster' (I've seen this before).
'wearing' becomes 'in' (as in being 'in' certain clothes).
'tail' indicates one should take the final letters.
The final letter of 'pig' is 'g'.
'oyster'+'in'+'g'='OYSTERING'

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.

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