We first noticed it when he was born. A zig-zag line running through his skin and towards his neck, tagged with a single, metal zipper. It dangled in the wind, bouncing happily as he giggled and waved his hands in the air.

At first I wondered what is hidden within my son, what secrets he was born with. But morbid curiosity soon gave way to concern about my son’s well-being. If I pulled open the zipper, what would happen to him? Will he die in agony because I had ripped him apart?

Therefore, I did my best to ignore it. It was easy. The zipper faded into a natural part of him, camouflaged into his skin. Besides the zipper, he was perfectly healthy in every way. Nothing abnormal about him.

Then I heard loud, raucous giggles.

They were unearthly, unethereal, echoing off the corners and walls of the room and burying deep into my skin. They sent cold shivers up my spine and made my hair stand on end.

They went on for nights on end, all the way until dawn. I thought my son, Zippy, had woken up in the middle of the night and demanded my attention, but when I went to check on him, he was peacefully sleeping, his stuffed donkey’s hoof stuffed into his mouth. I thought the house was possessed, so I hired a medium and a priest, but both assured me the house had no spirits.

Then I found bloody footprints everywhere, even up the walls. They all seemed to stem from Zippy’s crib, and the sheets were always soaked crimson, no matter how many times I changed it. A couple of times I saw Zippy sitting in a pool of his own blood. And once or twice I saw the zipper slightly ajar, blood staining his clothes.

The last straw was when I was away at a work dinner party, leaving my wife to care for my son. I came home to a massacre.

My wife was sprawled on the floor, her face half-chewed and showing parts of bone. Her eyes were gouged out, leaving a pair of gleaming black holes, and blood was oozing out of her mouth. Her teeth were cracked and some were missing.

Once again, curiosity burned my mind, and it quickly became an obsession. I tossed and turned in bed, wondering what was living under that zipper. A parasite, maybe, sucking out the life of my son, and indeed, he was not so lively these days.

Until one day I couldn’t take it anymore. While the laughter ripped my eardrums I crept into Zippy’s room and rolled him on his back.

The zipper was completely open, revealing an abysmal void cloaked in shadow. From within the giggles erupted, loud and clear like from a cave.

I peered deeper to look.

Then two shadowy claws grabbed my face, dragging me deeper still into its depths.