She Sold the Wrong Soul

Casey knew she had made a horrible mistake only moments after the deal was set. “All I want is him gone forever, and I want her to never date a person who is less than perfect for her.” She spoke the words she would dread and regret the rest of her life. His only reply, “Whatever you want darling.”
She had heard of making deals with the devil but never knew exactly how. The more she searched for information about it, the more signs she seemed to get. At first it was little things such as strange glances from random people around town that sent chills down her spine, as if she had stepped into a cold room, but it soon developed into hearing whispers in her ear as people would pass by, or her vision blurring out words and changing them into something of His. The signs were latent and she would only get them every now and then, but no matter how scared it made her feel, she knew she had to do something to help her family.

You see, Casey had a sister named Kate. She was as beautiful as the first spring flower, sweet as a lollipop, and as smart as Einstein! She could get any guy in the world, but she had a tendency to go for the lowest of low scum bags that only cared about themselves. No matter how many people would talk to Kate, and word their opinions on her choice in men, Kate felt she knew best and could change them for the better, or that all her family was wrong, and the boys she chose were wonderful and nobody could see it but her. All of Kate’s family assumed it was just a phase and she would grow out of it. Regardless of it all Casey and Kate were inseparable.
Over time Kate had started seeing a boy named Tommy, who after only months of being with her had proved to her family that he was all wrong for her. The family was more than ambivalent about him. He didn’t respect her or her family, he tried to isolate Kate from her family and friends, and was overall trying to control her completely and take full say over what she did, as if she were her property. Casey could feel her and her sister’s relationship slowly falling apart, and watching her sister step closer and closer into Tommy’s trap devastated her. When an engagement was arranged for Tommy and Kate, Casey knew she had to step in and do something, but just talking to her sister wasn’t quite good enough.
After seeing the signs more often than normal she looked up how to call the spirits and arrange the deal. She knew she had to word her deal carefully, and be very surreptitious about her plan. She wanted the devil to take Tommy, she wanted him forever out of their lives and she didn’t care what the consequences were as long as her sister never dated anyone who was the less than perfect for her. It was a very unscrupulous decision that she would soon regret.
The devil came through with his deal, the next day Tommy up and disappeared, he was never to be seen, or heard of again. But a deal with the devil couldn’t be just as plain and simple as that. It gave Casey a visceral feeling. What was waiting to come was something Casey had never thought of. Kate was the only person who knew who was perfect for her, and Tommy was it. Kate went into a great depression and committed suicide. Casey ruined the lives of everyone in her family and took the life of the one she loved and cared most about simply because she couldn’t stop to look and see who she was ‘helping’. The devil had won, like always.