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The Shadows bite - Creepypasta oc

(Warning! This OC IS in the supernatural part of the Creepypastas)
Name: Haley Jeno
Creepypasta Name: The Shadow's Bite
Age: 23
Gender: Female
Height: 5 ft
Creator: @foxyplusme
Weight: Unknown
Eye-color: Unknown
Body Shape: Skinny
Hair Color: Unknown
Skin Color: Unknown
Apparel: A dark green hooded vest, black half fingered gloves, blue jeans, a kitsune mask, and combat boots.
Personality: Well, she's not very social and doesn't really like to be near people unless they're victims. She's cunning, observant, hyper intelligent, thoughtful, fast, and she is good at making plans. It's quite an achievement if you survive her murders. Because of the lack of real social interaction, there is no clear description of how she acts around people normally.
Extra: She is inhumanely flexible to the point that it's a bit scary. (She's a contortionist)
Bio: It's said that Haley was young and had several things that were wrong with her. One, her flexibility was through the roofs. Second? She rarely ever spoke and people found it quite disturbing. When she got older, doctors tried to do surgeries on her but oddly enough, she would never fall asleep from the drugs. They did an experiment where they stuck her in a room with two other people. That night, when they turned out the lights, the two people with her disappeared and everything in the room was covered in blood. Except for Haley. One person went in with her with a night-vision cam but it blacked out for a second before the room was recoated in fresh blood. There were never any bodies, no screams, nothing. One night, the whole facility people left and turned the lights off by mistake. Only two guards were in the building and in the morning, only blood remained, leaving Haley to roam around, killing everything that strayed to the shadows.

Commentary: I honestly like this oc, but I'd like a bit more of a back round then just; SHE WAS BORN WITH THE POWERS OF SATAN AND SHE SHALL SMITE YOU.

Mary sue level: 25% Mary sue