As I crossed toward the park at the corner, I involuntarily turned my head because of a burst of light that had ricocheted from the window, and saw, with that quick smile with which we greet a rainbow or a rose, a blindingly white parallelogram of sky being unloaded from the van—a dresser with mirrors across which, as across a cinema screen, passed a flawlessly clear reflection of boughs sliding and swaying not arboreally, but with a human vacillation, produced by the nature of those who were carrying this sky, these boughs, this gliding façade. And there it was. Something indescribable, under the bridge.

If hideous was a place on a map then the creature before me was the atlas. From it's long, bent nose, broken in several fights, to it's pointed torn ears and missing teeth, it was your worst nightmare written large. But when it smiled I knew I was in trouble.

The smell hits you first, a rotten sweet putrid smell that takes the oxygen out of the air and makes you retch.
Then you see it, the face covered in long thick hair, the rotting teeth, the massive crushed and bent nose, the scars and open wounds covered in flies. It's eyes are abnormally large, bulging, full of hate and evil.
It spits at you as it steps out, blocking your path and fear hits you like a tree, making it impossible to move as it moves toward you, it's massive club raised to crush you like a bug. The earth shakes with every step and you scream as the club comes down.

Menacing as a wild animal

Fearless as a lion waiting to pounce on its prey.

Grousine as your worst nightmare.

Bug eyes protruding from a face covered with a wiry hair/fur mixture.
Long talons on the ends of stumpy forelimbs.
It has a two foot long, bald knobby tail which is constantly thumping the ground.