Whenever Halloween approached, Hogwarts would always be promptly decorated with numerous pumpkins, all the work of the house-elves. Olivia wasn't sure exactly how many house-elves there were in the castle; those in the kitchen seemed to be just a portion. Perhaps it was because of their large numbers that the Halloween decorations differed each time.
Olivia had only experienced Hogwarts' Halloween celebration once in her fifth year. To be honest, compared to the Muggle world she had once lived in, the wizarding world's Halloween was somewhat boring. There was no trick-or-treating, no candy, and certainly no costume parties that Muggles loved most. They would dress up as various ghosts and monsters to ask for candy, while others simply wanted to play pranks. Olivia was often frightened by William's costumes when she was young—not because his disguises were truly terrifying, but because of his behavior, suddenly jumping out and shouting to scare her. Her brother was incredibly annoying. In the wizarding world, people seemed to only have feasts and banquets, at least that's how celebrations were at Hogwarts. William, who loved to play pranks to his heart's content on Halloween, had complained to her many times that wizards' inability to experience Muggle joys was a tremendous regret.
Although there was no costume party, Hogwarts' Halloween banquet was still eagerly anticipated by students. On one hand, the dinner on this day was more elaborate than usual; on the other hand, there was the performance at the end of the banquet. Even the stern and boring Headmaster Black would kindly arrange a series of interesting shows. Of course, students were more inclined to believe this was arranged by Professor Weasley, with Headmaster Black taking all the credit alone.
Sebastian clearly wasn't as enthusiastic. After Potions class ended, while Olivia was still organizing her materials, Sebastian was shoving his things haphazardly into his bag. She suspected he might spill some potions on it, but Sebastian didn't seem to care. He leaned over with an expression that clearly signaled he was looking for trouble and asked in a low voice, "Hey, want to experience Halloween somewhere else tonight?"
Olivia wondered what after-class activity he was planning now: "Only if this won't make us continue copying that incomprehensible material for Professor Sharp."
Well, she was blaming Sebastian for their previous after-class activity that had gotten them both detention. "That was an accident! If we hadn't run into Weasley..." Sebastian was somewhat indignant. They had planned to sneak off campus after curfew last time. The whole thing was rather ridiculous—they just wanted to see the meteor shower near the Black Lake, with Sebastian explaining it would be more spectacular there. But as soon as they emerged from the dungeons, they ran into Gareth, who was also sneaking out at midnight. Gareth, for some reason, insisted on joining them. Sebastian hadn't counted him as part of their stargazing group at all, and the lion and snake bickered back and forth. Olivia tried to get them to be quiet, completely failing to notice the prefect had already heard them and was approaching. In the end, they didn't see the meteors but were forced to study a pile of obscure potion materials, and they never figured out what Gareth had originally been up to that night.
Olivia didn't wait for him to continue, grabbed her organized bag, and walked out of the classroom. Sebastian followed closely, walking alongside Olivia, his arm occasionally brushing against her shoulder. He continued explaining his plan: "I promise you, no off-campus adventures this time, and no detention either."
Olivia finally looked up at him: "What could make you give up the Halloween dinner?"
Big thanks to @eternalremorse for her post listing all of MC's classmates, it saved me most of the prepwork for this little project.
Priscilla Wakefield is not in any of the potions classes, at any time. I've replayed both several dozen times, and yes, I know there's a screenshot of her talking to Imelda on the wiki, I don't know when and how that was taken, but from what I can tell, she doesn't exist (at least not in any way that matters)
Also, I didn't include anyone who only shows up in flying class and nowhere else, as the attendance of Sophronia Franklin (who's confirmed to be a third year) definitively proves that that class isn't exclusively for fifth years.
I hope it's obvious that "unidentified student" is MC, I wanted to include them somehow (and had the row to fill anyways)
