Let´s kill someone

The sound of frantic footsteps echoed through a deserted alley. Two shadows darted across the rooftop and silently crawled down the gutter. The panicking girl looked over her shoulder and started to breathe faster. Her hands were sweaty and her heart was racing so fast, she could hear it. She gulped. A few steps later, she looked around again,only to find the alley completely empty. She giggled nervously. How stupid of her, to be so scared. Nothing is going to happen to her, she is just a few more minutes away from home. She slowed her pace and started to breathe normaly.
But as soon as she relaxed, she noticed a dark figure at the end of the road. She blinked and looked again. He was gone. Or perhaps he had never been there. Perhaps it was a hallucination. But then, she heard a hushed whispering, just behind her. She frantically turned around and noticed a tall woman. Her eyes were shining, even though there were no lights anywhere near. Her hair, long and curly, ware slowly moving with the wind. She was smiling softly.
Suddenly the woman´s eyes focused on something behind her. Her smile turned into a huge, almost crazy grin. Just a second later, the girl felt a stinging pain in her back, as someone hit her. She landed on the floor with a soft ´thud´ . Her eyes widened when she caught a sight of a woman and a man standing above her,smirking in satisfaction.

˝ P-p-please, don´t h-hurt me ˝she stuttered quietly.

There was a tense silence for some seconds before the woman started to laugh. She was laughing so hard, her eyes watered.

˝ Stop it Amy ˝ Matthew said, after a while.

He wanted to kill already. He wanted to see the blood, to hear the pleading screams. His crazy sister was already getting on his nerves. But Amy just kept on laughing. The cold laughter echoed inside his head and he felt like he was going crazy.
He couldn´t take it anymore. He pulled the knife out of his pocket. He hesitated for a moment but then lifted his arm, ready to stab. But at that moment, the world started to spin. An excruciating pain shot through his head as he fell on his knees. Amy´s laughter started to fade. Matthew looked into her eyes and breathed for the last time. The last thing he saw were her cold, emotionless eyes. Then his head hit the pavement.

The girl started to scream. She was now certain that she will die, today. And this woman,this crazy woman, was going to kill her like she killed that man.
She herd a soft whisper: ˝ Don´t worry, I´ll make it quick, sweetheart ˝

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As dawn broke the sky with flashes of pink, and the melancholy sound of a distant train cut through the cold morning air, the police found two cold bodies, laying in the sewer.

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