I guess you could call this AU, seeing as I've written it so that changes witches sides between Light and Dark quite frequently, and isn't a double agent.
I don't own Harry Potter, or any of the other random things referenced in this.
It wasn't Dumbledore's dress sense that had driven Snape to the dark side. Nor was it the headmaster's tendency to assume that a nice singalong was the way to sort out any difficulty in Hogwarts, be it Gryff/Slyth tension or a rabid bear wandering the corridors. No, Snape decided with a shudder, it was the lemon drops. When he had first been interviewed for a teaching job at Hogwarts, Dumbledore had offered him a lemon drop. Snape had politely explained that he didn't like them,and that had been the end of it. Or so he had thought.
Snape had been called back to the castle a few weeks later, congratulated on getting the position of potions master,and been offered a lemon drop. From then on,it seemed like every time he ran into Dumbledore, the headmaster had a bag of the vile yellow things on hand, just waiting to torment him with. Finally, Snape had snapped, hexed the lemon drops into a pile of dust, and delivered a long rant about how much he hated lemon drops, Dumbledore and the school in general. Dumbledore had sat silently through his tirade, and when he was finished, calmly invited him to take a seat and discuss things like grown-ups - and offered him a lemon drop.
That night, Snape left Hogwarts and pledged his service to Voldemort. Sure, You-Know-Who may be a few Sickles short of a Galleon, but surely he couldn't be as crazy as Dumbledore.
Snape had never been so wrong in his life.
It wasn't just that Voldemort enjoyed ambushing his Death Eaters and claiming to be their father. Snape could handle that. He could even handle his new employer grabbing him by the shoulders and asking him intensely if he could hear the sound of the drums. Lucius Malfoy's peacock obsession was a bit weird, but then Snape didn't have to interact with him too often. Actually, most of the Death Eaters had their own strange habits, but Snape felt he couldn't really complain as he now twitched nervously whenever someone mentioned the words "lemon drop". In fact, he suspected Voldemort of code-naming his plan to kill the Potters "project lemon drop" purely to drive Snape closer to a nervous breakdown. It was working.
The day Snape finally cracked and returned to Dumbledore was the day Voldemort had made him spend an evening running around the English countryside shrieking, 'Ssshire...Bagginsssss!'
Some of the Hogwarts staff had been sceptical about the sincerity of Snape's return to the Light side, but Dumbledore had got them all to sing "Kumbaya" together, and after that nobody had voiced any objections, possibly because they feared that Dumbledore would make them sing again.
Snape stayed on as a teacher for many years, and whenever it started to feel like Dumbledore's sole purpose in life was to annoy his potions master to the brink of madness, he remembered the time Voldemort had decided to form his own basketball team. After that, Snape, was confident that he could handle anything Hogwarts could throw at him. Then came the Boy Who Lived.
Snape was certain that, while the boy appeared to have the intelligence of a flea, he wasn't nearly as bad at potions as he pretended to be. In fact, Snape would have bet his "Voldie's Vipers" basketball hoodie that Harry Potter was in fact quite skilled with potions, and was channelling this skill into antagonising Snape. What other explanation was there for the way all of Potter's potions blew up, leaving behind a cloud of yellow smoke that smelled strongly of lemons and lingered in the Potions classroom for the rest of the day? Snape had taken this theory to the Headmaster. Dumbledore listened carefully, then told Snape that he was overreacting and would he like a lemon drop? Snape had burst into tears and the next day gone back to join Voldemort. At least the basketball team didn't involve lemon drops...
