Beast in the Alley! (Patreon)

He had heard noises for the last few minutes. Odd gargling, slurping, slithering noises, with heavy bangs and thumps emanating from the alleyway at the back of his shop, so he grabbed a flashlight and went to see what was there. "Probably some kids beating on the shutters and barrels in the trash", he thought.

He stopped at the mouth of the alley and looked beyond to the end row of windows by the shutters. There, facing away from him crouched a gargantuan anthracite coloured mass, only partially illuminated by the streetlight above it. Taking a few hesitant steps closer and shining his flashlight at it, he managed to get a closer look at the hulking creature.
It's skin writhed; it's muscles rippled and knotted; he could see the carpet of veins that crossed it's back throb and pulse as its whole body shuddered and tensed.

"What are you?" he whispered to himself quizzically, but immediately froze as the creature stopped moving.
With haste he cupped his flashlight to smother the light and held his breath. Panicking, he began stepping backwards as fast and as quietly as he could. After getting several metres away from the beast, his foot ricocheted off of a small rusted trash can, causing the creature to immediately rise and begin to turn.

Watching in horror, he saw that it was sporting a gargantuan erection, with balls that scraped along the floor as it turned. It's body was pure muscle, it's tongue undulated as it began to open it's maw. His eyes looked up to meet with its own just as the beast let loose an earth crumbling howl.

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