Sirius lunged forward and closed his hands around her throat, smashing her head into the stone wall behind her. He ignored her yelp of surprise and the scrabbling of her fingernails against his wrists, focusing instead with glee on her bugged-out eyes and the changing hue of her skin. It took only several seconds for her eyes to shut and her resistance to cease. She wasn't dead yet, though, just unconscious. He would have to stay there for another few minutes before she would die.