Holy shit-a-brick, why didn't anyone tell me about these things YEARS AGO!?!? If you don't know what a Creepy-Pasta is, it's basically a short horror story or collection of stories surrounding a scary subject. Creepy-Pastas are basically online urban legends and folklore, there's even a term for phenomena like Slenderman called "fake-lore." Fake-lore is, pretty much, exactly what it's spelled out as.
I can't stop reading these things, these short little stories are addictive. There are even Narrators that get paid (mostly via Patreon) to read them on YouTube or other Internet media.
THIS is my favorite one of all time so far: I should warn you, it's extremely disturbing...
It's also a long one, but it's divided into sections jike entries from a blog or journal. So if you want to take a break after each entry, it's easy to do so.