Bloody Reunion (Bullied!Oliver x Bully!Reader)

You were been invited to a school reunion after school by your best friend and your crush, Oliver. But then, headache start attack you and fell unconsious.
Since the headache, something bad start as one by one, your friends been killed. You even got a same nightmare everytime you sleep.
What did just happen? Why did your friends been killed? What is the killer wants? Who is the killer and most importantly, who are you actually?

P/S: Contain blood scene, gore, killing, maybe will have poison and many more. So, to those who don't really like this type, don't read! And I mean it!
Oh, and one more thing, this is not a yandere story. That's all.