This one can be done in many ways. Freezing someone just full out would be a bit faster, but they won't feel much pain. This is for someone you hate, so why make it painless? The best way and the most painful way of doing this is freezing the said person until they are almost dead and then warming them up quickly like using a fire or using a thicc blanket.

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I held her hair tightly in my grasp as she tried to scream and get out of my grasp. She wasn't going to do it this time. She had already escaped once and she almost got me caught. I can't let that happen.
I smiled at her as I dragged her down the stairs, her body flailing around and trying to hit me. A sadistic smile on my face, I finally got to the bottom of the basement stairs. I hummed as I saw the old fridge I had down there, and I dragged her body to it. I set her down, opening the freezer with a hum.
I groaned inwardly, seeing a corpse with pale skin and blue lips sitting in the freezer. "God dammit I left him in there." I muttered, taking the body out and throwing it in a corner with the rest of the mangled corpses. They were starting to smell, I'd have to get rid of them soon. Although only 5 bodies lay, I was about to add another.
I grabbed the girl's hair again and I threw her into the freezer with a happy gleam. "Bye honey" I told my best friend as I kicked the door closed.
I hummed gently as I went over to my phone on the table, setting a timer. 20 minutes should do. Making my way to the small fireplace, I threw in a log of wood, and started dousing it in gasoline. Grabbing a match, I flicked it into the fireplace.
I sat down in a comfy chair, turning on my phone and started playing Minecraft as I waited for my timer, faint struggling coming from the freezer. Soon, the timer went off in my phone and I felt a bit bummed, it felt like such little time. I set my phone down and made my way to the freezer, opening it.
The girl I called my best friend for the longest time lay there, her cheeks red and her lips blue. Frozen tears were on her cheeks as her eyes were closed. I picked her up by the hair again, and I dragged her out and over to the fireplace, wrapping her body in a thicc blanket. I watched as her eyes opened, her mouth trying to scream as she fell over from the pain.
I hummed as I watched the color return just a tiny bit before the 10 minute timer I had set went off. I picked her up again, her head shaking wildly as I shoved her back into the freezer.
Repeating the process I had been doing, freezing, setting a timer, playing Minecraft, getting her out, setting her in front of the fire, and then putting her back in. It was a bit boring but she finally gave up, her body stuttering as I got her out one last time.
I sighed "You were a fun one for a big, dearie." And then I laughed, looking at her and grabbing a pole. The other one had died already but she wasn't dead yet so, I shoved he pole into her head like I was gigging a frog.
Laughing as the blood spilled out a bit when I pulled the rusty pole out, her breathing stopping. Now, I had to get rid of the all bodies I had gathered...