Disclaimer: I don't own any of the Harry Potter people or the Hogwarts school song. :(
Severus' Turn
Severus Snape carefully read the directions for the potion he was secretly brewing in the Room of Requirement: the Elixir to Induce Euphoria. If he messed this up, it would be dreadful. This potion would be the most rewarding form of payback to ever occur at Hogwarts. But who would be the ones to drink it? The only reasonable answer is Sirius Black and James Potter. Merlin knows they deserved it.
The Next Morning at Breakfast in the Great Hall
James and Sirius walked in with the other marauders and sat down in their usual seats at the Gryffindor table to begin their breakfast. Across the room, Severus smirked at their obliviousness. It had been surprisingly easy to slip part of the potion into each boy's drink. As if destined, James and Sirius simultaneously picked up their cups and drank their "orange juice." The effects were immediate; both boys began to smile widely, and their eyes glowed with excitement. Lupin stared at Sirius with curiosity; the only times Sirius smiled was when he harassed Snape. But no one else seemed to notice anything out of the ordinary. Severus Snape was afraid that he wouldn't succeed.
"Of course," Severus thought, "the one time I'm positive I'll succeed at a prank, I fail. How characteristic!"
While Severus continued his rant inside his head, students ran into the hall to stare at the Gryffindors. Sirius Black and James Potter were standing on the table, shouting to the students.
"Hello Hogwarts! I don't know if you all know us, but I'm James and this is my best friend, Sirius. We don't know what happened, but we feel GREAT! So, we're going to sing a little song for our marvelous school."
"YEA," shouted Sirius.
Severus Snape and the rest of the Slytherins were laughing before the first lyrics rung out. This was awesome! Then, they boys started singing the one song that every Hogwarts student was embarrassed to know.
"Hogwarts Hogwarts Hoggy Wortty Hogwarts
Teach us something please-
weather we be old and bald
or young with scabby knees-"
Students were laughing hysterically as the boys continued to sing; the best part: they were tone-deaf. Just as everyone thought it could not get better, Professor McGonagall walked into the Great Hall with a look of astonishment.
"James Potter and Sirius Black, WHAT DO YOU THINK YOU ARE AHHH," she yelled as Sirius ran up to her, grabbed her waist, pulled her close to him, and attempted to waltz around the room with her. Then the laughter increased; when McGonagall pushed Sirius away , James ran up to take her place. Meanwhile, other teachers ran in and commanded that they stop immediately.
Sirius was singing again; this time, he told James that the giant squid, which was living in the lake, needed someone to swim with.
"This is more than expected," Severus thought, "and I'm loving it! They practically asked for this. Revenge is sweet."
Soon class would start, but the potion wouldn't wear off until night. Although everyone wouldn't be able to see them the whole day, for once, Severus Snape was happy to have class with the marauders. Even if he were punished for his prank, every moment would be worth it. This day was so great that it would not be forgotten for many years.
The End