So...(spoilers spoilers spoilers)
Spoilers. Arf.
Cossette wasn't Cossette, Cossette was the painted image(s) of Cossette.
Now...why would the painted image of Cossette care if Cossette was murdered?
Well, I think in the first place it was the real Cossette until she left Eiri and the Portrait took her place..
Or, well, Maybe the Portraits wanted to be redrawn and be the center of attention?
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