Rules ignored while putting together rogues' gallery - it looks grotesque (8)

I believe the answer is:

gargoyle

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'grotesque' is the definition.
(I've seen this in another clue)

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

(Other definitions for gargoyle that I've seen before include "Grotesque face as an architectural feature" , "Ugly spouting face?" , "grotesque sight!" , "It drains off water" , "Grotesque-looking waterspout" .)

I've seen this clue in The Irish Times.

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