Check over your story. Editing is important. Your spelling needs some work, honey.
Grammar and Syntax is also a bit of an issue here. It should be 'The Most Evil' because 'Evilest' isn't a word.
Your character...is sort...of...a Mary Sue. There is literally no way to go about this delicately. Situations don't flaw a person, it's how a person reacts that makes them flawed. Her dad was murdered in front of her? AND SHE COMES AWAY WITH NO MENTAL ILLNESSES?
No! This will not do!
Coping mechanisms, OCD, PTSD, Dissociative Identity disorder, something! The lack of trust is a good start. You could work around that.
Why is she in Slytherin? Don't let the answer to that be, "Because it's awesome." Personal drive? Sociopathy (tricky to write, but fun!)? Does she want adoration?
Green combat boots? Stick to the dress code!
These are just suggestions. Change it, don't change it, whatever. Do as you please.