Double Black

The Amortentia Incident

It was common knowledge that Dazai and Chuuya were sworn rivals. Pretty much every single student in Hogwarts knew. The teachers who conducted both their classes during the same hour knew as well. After all, they never tried to hide it. 

Nakahara Chuuya, fourth year at Hogwarts, member of Gryffindor and Seeker for the Gryffindor Quidditch team. He was a short boy with vibrant read hair, ocean blue eyes, and a clear obsession for hats and butterbeer. He was rather short-tempered (pun absolutely intended) and would rather get into trouble than staying quite when provoked by his sworn enemy Dazai.

When Chuuya was strictly kept away from Dazai, he was very pleasant to be around. He was nice to everyone, was really kind and helpful, and even though he swore in literally every sentence he spoke, it wasn't in a mean way. In fact, it was funny and all his friends found it amusing. Speaking of friends, he had lots of them. 

Yosano Akiko, the Gryffindor sixth year, and Akutagawa Gin, the Gryffindor second year, were both quite good friends of Chuuya. He was also friends with a few Hufflepuffs, namely two boys named Nakajima Atsushi and Tachihara Michizou. There were also two other Ravenclaws, who Chuuya knew well enough, but he wasn't very to close to them. Kunikida Doppo and Edogawa Ranpo were more of Dazai's friends. And Chuuya wanted nothing to do with that shitty asshole. 

On the other hand, Dazai Osamu was a fourth year at Hogwarts as well, member of Slytherin and of the opinion that "Sports are stupid. Why would I want to watch people flinging around a bunch of hazardous balls?" He was rather tall, his brown hair almost always perfectly tousled, and his brown eyes always hinted with the Slytherin brand of evil. He was an absolute genius; top of every single class he took with zero efforts. In fact, everyone knew him to be the Demon Prodigy from Slytherin. 

Every visible part of his body, other than his face, was always covered with bandages. Tendrils of white gauze curled up his neck, down his hands and everywhere in between. Nobody had ever figured out if he wore bandages for medical purposes, or if they were merely an accessory. Other than that, it appeared that Dazai's one purpose in life was to be a constant annoyance to everyone around him. Despite that, he had a few friends too, for some reason.

The Slytherin third year Akutagawa Ryuunosuke practically worshiped the ground Dazai walked on. But one wouldn't say that they were exactly friends. The Ravenclaws Kunikida and Ranpo hung out with him sometimes, much to the former's annoyance. Ranpo however, was just as much of a genius as Dazai, and hence the two of them usually got along pretty well. The Hufflepuff boy, Miyazawa Kenji, who liked literally everyone, hung out with him as well. Surprisingly, Dazai didn't mind his presence at all. 

Despite having these four "friends", the Prodigy genius wasn't very close to any of them. However, there was one person who he would genuinely consider as a friend, and that was Kouyou Ozaki, Slytherin sixth year. She was alright. Dazai didn't mind her as much. 

Anyway, the point is that Dazai and Chuuya did not get along. Everybody knew that. They were sworn rivals, ready to kill each other at any given point of time. And that is exactly why the whole school was taken by horrid surprise when "The Amortentia Incident" happened. 

The day started like any other. Everyone had breakfast in the Great Hall before going off to their respective classes. After hours of gruelling classes, the final period arrived. The Gryffindor and Slytherin fourth years had Potions with Professor Snape as their last class of the day. The situation would be fine if Dazai and Chuuya weren't in this class too. But of course, they were in the class, and worse, they were partners.

Since Professor Snape liked to torture his students, he'd fixed everybody's class partner for the year on the very first day of their fourth year at Hogwarts. Since most of Dazai and Chuuya's friends from their own house were not in the same year as them, those two had ended up sitting next to each other on their first combined Potions class of the year. Obviously, Professor Snape just had to pair them up; he knew of their rivalry very well, but of course, he wouldn't be Snape if he didn't go against his students' wishes, right?