Hers.
Time slows, stretching like toffee. Years of being ensnarled in the mundane dulls the senses, but now, in this ever lengthing second you are more alive than ever. The moment gets drawn out, thinner and thinner into a white hot thread, and all the air is gone and your lungs are on fire, and the figures around you slow to statues. And then...
...when there is nothing more that can be crammed into this eyeblink, this eternity...
...then the magnesium flare snaps, and you are running faster than you thought possible, screaming a challenge at the top of your lungs.
"NOT MY DAUGHTER, YOU BITCH!"
They are frozen, a tableau of fear and defiance in the face of evil. You wonder, looking at them, how can evil be so immaculate and beautiful, while the good is so tearstreaked and dishevelled and more precious to you than life itself?
"OUT OF MY WAY!" you screech, a banshee wail, willing your cherished daughter and her friends to move. They scatter like leaves before a gale, leaving you a clear path to where she stands, laughing that someone as ordinary as you would dare challenge her.
For years your grimoire has been a recipe book, your potions lab a cosy kitchen and your duelling ground a gnome-infested garden, but all the time that has passed is nothing, and you are a battlehardened witch of the Order once again. Your wand is a blur as you cast curses and countercurses, animal, instinctive actions faster that your conscious mind can follow.
You sense, rather than see, a few brave souls edging closer.
"No!" you shriek, hoping they'll have enough sense to get out of your way. "Get back, get back!" If they come any closer you're worried they'll be hurt, and enough children have died today. Fred. Let this deatheater whore face an equal fight for once.
"She is MINE!" you shout. The right is yours. She is Voldemort's creature, and he has taken too many of those dear to you for it to go unpunished. It is time to repay him tenfold and take those closest to him. At this moment, you are vengance given form, a lioness in defense of her cubs.
"What will happen to your children when I've killed you?" her taunts seem foolish, and you realise with a jolt that you are fighting to the death with an opponent who has a broken, child's mind in her woman's body. She is still throwing words at you, but they slide past, unheeded. "When mummy's gone the same way as Freddie?" And at that moment you know, with a crystal certainty, that this is where it ends. It seems almost too easy, as the foolish, pitiable child before you gloats and taunts, to raise your wand.
"You-will-never-touch-our-children-again!" You cry, and she laughs. The poor madwoman is laughing in your face as your curse flies straight and true. It passes beneath her trembling, outflung arm and strikes her, a killing blow. Above frozen lips, still curled in a misplaced smile, you fleetingly see realisation dawn in her eyes before she crumples to the ground.
An inhuman scream splits the air, but Voldemort's agony is of no consequence to you. The roar of triumph from those around you passes through you without acknowledgement. Your mind is filled with just one, triumphant thought.
Bellatrix will never touch your children again.