Things are not what they seem (Doom Slayer x Oc)

Prologe

Narrator's P.O.V
The sun hit the eyelids of a 29 year old girl, she lets out a groin and throws her paper white arm over her eyes. Okay okay so this girl's name is Scarlet and she's half marauder, having horns, and paper white skin, and goat hooves like her father but golden eyes and black hair that are from her mother, and at a staggering 9 1/2 feet she dwarf a lot of people. Then there's her sister heaven who has light brown skin, and black hair like their mother but black eyes with red pupils, and goat hooves like their father, and standing at 5 foot 2in in height. The girls thought this would be a normal day for their family but things were going to get a lot worse for them.

Scarlet's P.O.V~
I open my eyes and look at my clock 5:00 am, 'Why the f**ck am I up at this ungodly hour of the morning' I think to myself. 'Nightmare the same one I've been having for weeks now'  fire is everywhere mom and dad's corpses are on the floor a marauder is standing over them he turns and looks me straight in the eye and laughs at me cause he knows I can't do anything he starts to say something but I always wake up before I get to hear him.
She gets out of bed and goes down stairs she grabs her cloak and her dog, and heads out of the house the sun is just starting to rise and people are just getting off work or just going out to work. 'So peaceful this early in the morning.' Scarlet thought to herself as she started to walk down the street her cloak hiding her body from the few people that were out and about.
                           ~time skip few hours~
Scarlet entered her home with a light sigh of joy at the sound of her mother in the kitchen. "Scarlet this is the fifth day you've been going out for a walk in the morning are you feeling okay?" Scarlet's father asked. "Yay I'm fine just been waking up early and I can't go back to sleep so I just go for a walk instead." Scarlet replied
                 ~time skip to mid day ~
Heaven and I are in the backyard training with our crucible weapons when chaos brakes lose. Demons started to appear in our backyard so I killed them and grabbed heaven and ran inside of the house, I was just about to call out for mother and father when I heard them scream I rushed to my parents room. 'This is just like my dream please don't be dead please don't be dead please ple— no no no no no' I got to the doorway and there on the floor my parents corpses with a marauder standing over them he turned to me and started to laugh. "You must be Scarlet one of my nieces I am your uncle and I'm here to kill you." He stated. 

Narrator's P.O.V~
Scarlet blinded by fury took her crucible mace out and charged at him. After a grueling fight she killed her so called uncle and gathered up her sister and her dog and fled the house.

            ~one week later ~
(Play the song now)
Sis I miss mommy and daddy heaven stated I know I know Scarlet replied a week ago their parents were killed by their uncle and their uncle killed by Scarlet. Now they are inside a lookout they made their shelter their dog rover has also mutated and is big enough for Scarlet to ride demons were everywhere and they had to kill a lot of them multiple times a day but heaven was safe and that's all that matters to scarlet. Because all scarlet has left of her family is her dog and her little sister heaven and she will kill anyone who try's to take them away from her.

Or so she thought.