If the world went backwards - Issac foster X reader

See you soon Rachel

Issac (zack) POV

I looked down to see pure terror in her eyes. This only made me more excited, I couldn't wait to kill her! I raised my knife. In a split second the fear turned to lifelessness as she look up at me. I couldn't help it, all I could think about was Rachel.
About the time we spent trying to get out of that hell hole of a building. There I had learned that I wasn't the only one insane, and that she too had done some messed up things.

*time skip* *before Zack met (Y/n)*

We had made a pact of in order for her help in escaping the building that I would kill her. We had gotten out of the building, Rachel almost dead as it was. The police had surround us, I was taken into custody for the supposed kidnapping of Rachel Gardener, and Rachel was taken to a medical facility that was meant to help with her mental disorder. I knew I made a promise, and I was a lot of things such as a psychotic murderer, but I was never one to fall through with promises. I had escaped the prison and made my way to the hospital to find Rachel. After searching through what felt like 10,000 windows I found an open one, and there on the bed sat Rachel Gardener. I spoke up to her and she turned her head relief flooding her eyes. It sparked something in me. I reached my hand out and she took it without hesitation. I grabbed her a jumped out the window somehow managing to dodge the police cars that had arrived. I made a break for the woods with Rachel under my arm. Zack, she said, you kept your promise. In truth I didn't want to. I wanted to keep her by my side for the rest of my sad life. I didn't say that though and instead responded with, ya, of course I'd did. You didn't doubt me did you? Then, for the first time, she genuinely smiled. She smiled! Of course if didn't. She said, here. She handed my the dagger I gave her. Here, Kill me with this. Part of me didn't want to, but a promise was a promise. So I raised the dagger and brought it down right through her heart. Thank you Zack. Thank- she said as the light slowly faded from her eyes. Then she was gone, and he was alone once more. He had lost the police a good while back, so he took his time with the dagger digging a hole and gently placing her inside of it, he tucked his dagger he had given her in her hands like a Bouquet of flowers. He brushed the dirt atop of her and with his finger wrote the words the best he could, Rachel Gardener. He didn't know how to write so it didn't look the best, but he had tried. Sorry Rachel, I know Eddie could have done a better job, but thank you too. See you soon Rachel, he said. He then continued on his way, not knowing where he would go or what he would do. He ultimately decided on a will to live, because that seemed like a great place to start.