Ava. This name can be used to create a character who seems sweet and innocent at first but is actually involved in something much darker. In a horror story, Ava might be luring people into a trap set by a malevolent force.
Luna. It has an otherworldly feel, like she could be a character with a mysterious past in the horror story. Maybe she's a girl who can see ghosts and Luna gives that sense of a connection to the night and the unknown.
Ella. A simple name that can be made spooky. Ella could be a girl who is constantly followed by a malevolent shadow in the horror story. The name gives an impression of vulnerability, which is perfect for a horror character.
Ophelia. It has a tragic and ghostly connotation. In a horror context, Ophelia could be a girl who has been haunted by a family curse or is a victim of some dark magic, her name adding to the overall sense of doom and gloom in the story.
How about 'Ella Blackwood'? The name 'Ella' gives a sense of femininity and vulnerability, while 'Blackwood' has a spooky, dark forest kind of feel. Another could be 'Victor Grimshaw'. 'Victor' is a strong but can be a bit old - fashioned name, and 'Grimshaw' just sounds menacing. And 'Luna Shadows', 'Luna' is often associated with the moon which has a lot of horror connotations like werewolves, and 'Shadows' adds to the eerie atmosphere.
Damien. It has a very dark and menacing feel, often associated with the devil in some horror concepts. Another one could be Cain, as in the story of Cain and Abel, which has a sense of primal sin and violence. And then there's Lucifer, which is a very obvious choice for a horror - related name as it is directly related to the devil in many religious and horror stories.
Cursed Reverie. 'Cursed' is a very strong word for horror, indicating that there is some sort of malevolent force at work. 'Reverie' which means a state of being lost in thought, gives the sense that the characters are trapped in a nightmarish dream - like state.
Some good names could be 'Damien'. It has an air of mystery and evil associated with it. Another one is 'Luna', which can be a bit deceiving as it sounds beautiful but can be used for a character with a dark side. Also, 'Victor' gives the impression of someone who might be involved in some unethical experiments, which is very fitting for a horror story.
Cursed Crypt. A crypt is already a place associated with death and the unknown, and adding 'cursed' makes it even more menacing. It could be a place where dark magic resides or where the dead don't rest.