You had a friend group where it was Tatum, Randy, Stu, Billy, and Sidney; Nobody expect Stu and Billy knew about who was the two Ghostface's who has an ongoing killing spree. You've been secretly obsessive over Billy and felt strong hatred against Sidney, he stole him from you because she accused you of having possession of marijuana in order to use those weeks of your suspension to get you out the picture in order to start dating Billy.
Everyone knew that Billy was only with her because he wanted to become popular and gain a loyal group of friends, which he now has. All those years of them being together, the more jealously and hatred you feel until one morning, it was 3:57 AM and you couldn't fall asleep. You needed to take Sidney out the picture, forever. You dig through your closet, finding an uncanny human mask that had a burnt face, it was a bit cracked, adding more to your insanity delusions. You put on a black jumpsuit with your hair in a bun, a hood, and the mask over.
You sneak into Sidney's house and sooner or later, Sidney is lifeless, but you continued to stab her repeatedly until, the door opens, and you see the infamous Ghostface's (Billy & Stu but you didn't know that) who came to kill Sidney, but you reached her first. You then pull your knife out her back, the blood trickling down your hands. You quickly fled the scene, afraid that the Ghostface's might kill you.
Weeks after Sidney's death, you slowly started making a list of all the girls who flirted with Billy and added it to your "Hit List". You were talking to the group when Casey (she isn't dead here yet) comes to Billy and kisses his cheek unexpectedly. This made your blood boil, and you zoomed out, not noticing that your baby blue eyes were boring into hers as she stood next to Billy. You thought, "I'm killing her tonight."
That's where the legacy of The Burner started.