Hyperactive Felix and mellow Hyunjin, who have never really met before but have heard of each other. Through a mutual friend the eventually actually meet.

   There are probably quite a few plot twist in this.

   Felix does leave at one point.

  Who is the mutual friend?

   Felix comes back engaged.

   Who is he engaged to?

   Why did he leave?

   What ending with this story have?

   Sad ending? Happy ending? Surprise major character death?

   That does sound fun.

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   Hyunjin and Felix have been best friends since since they were little. So when they grew up they decided to attend the same university. One night Felix jokingly suggests they go to couples therapy to see how long it would take the therapist to figure out they aren't in fact a couple.

  It backfires majorly.

   I know how this one ends so it is a little boring for me.

  Not angsty enough.

   I could make it angsty.

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   High school juniors Felix and Hyunjin who share geometry class. Hyunjin, who sits in the row next to Felix only a couple seats back, often catches Felix counting his fingers. One day after class their teacher asks Hyunjin to stay for a moment. That's when the teacher asks Hyunjin to tutor Felix.

He agrees thinking it would be easy.

  He's wrong, it is not easy. Felix is quite hyperactive and his attention span is short, leaving Hyunjin drained by the end, but even so Hyunjin finds Felix absolutely adorable.

   I know how this one ends too.

  This one is angsty.

   This won't be a story, probably just a oneshot.

-

    Hyunjin a university professor and Felix his teachers aide. Often times Hyunjin finds things where they shouldn't be or he finds that Felix gets distracted before he can finish with any tasks. While it does make Hyunjin's workload a little bit bigger, he still finds it endearing.

   -

  Cat hybrid Felix and human Hyunjin who are roommates. While most cat hybrids are quite mellow and prefer to sleep, Felix is a hyperactive ball of sunshine. Hyunjin oftentimes finds Felix sleeping in the oddest places for there dorm closest to a random box that Felix manages to fit himself into. Hyunjin finds it all endearing, the way he finds Felix in odd sleeping places and the odd small fixations Felix has on random things (like the origin of the lucky cat)

  I know how this ends, I think.

    This one gets a little sad.

  They argue. Felix sleeps outside at one point.