Elsa and Jack were ''boyfriend and girlfriend''. But really, they only wanted the sex from each other. And they always got it. And they only started at the beginning of their Junior Year in High School. They would do it, and never speak of it at school, but everyone knew that they were ''dating''. No problems.
Until one night when Jack broke up with Elsa, during their sex.
Elsa avoided Jack for years through High School, up to Senior Year. They both changed. Elsa changed her style and became shy and frail. Jack Frost changed his style and stayed as the pervert he was. Elsa and Jack are forced to talk and interact with each other during Senior Year because, now, they have all classes together and they sit next to each other in most of them. Elsa doesn't talk much but Jack always annoys her.
Then, one day, they were assigned a project with each other. Jack came over to Elsa's house unexpectedly when she was there alone.
And the sex cycle continues, only something is different.
You don't know how or why, but you've been isekai'd into the world of Jujutsu Kaisen. Although your first instinct is to stay far away from the plot, you've been blessed with an abnormal amount of cursed energy, and for better or worse, you find yourself sucked into the storyline. You decide that you may as well use your newfound powers for the greater good, and if you're lucky, you might succeed in rewriting some of the characters' fates. But it turns out that your presence in this world is even bigger deal than you first thought, and soon, everyone wants to make you theirs.