When Narcissa is told that Sirius is dead, she blinks and simply says, "I see." Then she continues to idly brush her hair as if it will brush away the hints of remorse that are tugging at her heart, begging to not be forgotton.
The fact that blood bonds them is significant. Or maybe it was, once upon a time. Because the true fact of the matter is that Sirius Black was a traitor to the family and therefore, dead to her. Yet the knowledge that he is not just mentally dead to her but literally is upsetting and her heart pounds in an unfamiliar way.
She lets the brush drop from her hand and takes a long, lingering glance at the beautiful image reflected toward her. She smiles. She frowns.
Her cousin is dead but what does it matter, anyhow? To survive in the wizarding world, you must choose a side. Narcissa had long ago chosen hers and would remain firmly on that side, despite any circumstances.
Sirius is dead.
Narcissa quietly raises from her vanity table.
She moves on.
But still, a tiny ache flares inside of her and refuses to be extinguished.