Pettish, unattractive persons? (4)

I believe the answer is:

dogs

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'persons?' is the definition.
(dog is a kind of person)

I don't understand the remainder of the clue.

(Other definitions for dogs that I've seen before include "Persistently follows" , "Shadows" , "Setters, for example" , "pets" , "Hounds" .)

I've seen this clue in the Evening Standard.

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