Everything you recognize belongs to JKR et al. Thank you, Maggie, for beta-reading and putting up with my silliness. This was written for jendeben aka mouse for a livejournal meme.
As every well-educated wizard knows, flobberworms are a common ingredient in potions. Therefore, it was not surprising that Neville Longbottom was sent to Hagrid's hut to get a fresh batch of flobberworms one evening in his seventh year while he was serving a detention. After Filch caught Neville snogging with Lavender Brown behind the statue of Hieronymus the Hasty, Neville thanked his fate and good fortune that the worst thing that could happen to him these days was a detention with Horace Slughorn. He shuddered to think of what he would have to do if the former Potions master, the murderer, were still in residence. He didn't need to think long; he had served detention with Severus Snape often enough to know that he would probably be gutting horned toads – without dragon hide gloves. But now Snape was who-knew-where, running around with You-Know-Who, and Neville hoped fervently that he would never have to see those creepy, tunnel-like, black eyes again.
Those same black eyes stared into his when he came back from Hagrid's, crossed the entrance hall, and opened the door to the corridor that led to the dungeons
With a shriek, Neville jumped back. The jar with the flobberworms had slipped from his fingers and shattered on the stone floor. For a moment he stood frozen, unable to grasp the significance of two hooded figures standing in the middle of the corridor with a blueish, glowing object in their hands. One of these figures stared at him, and the eyes that were gleaming in the shadow of the hood could only belong to one person. Neville let out another yelp, turned around, and ran away as fast as he could.
"We need to hurry, Master. The foolish boy will raise the alarm."
"Do not concern yourself with this, Severus. Do you think I would walk into a trap like some stupid Muggle? The rest of the school will be taken care of, and we will be undisturbed."
Snape nodded reverently and both men walked through the door into the entrance hall.
"What happens now, Master? You haven't informed me of your plans."
"Patience, Severus. You will see soon enough. Consider yourself honoured; you will be the first to see how Lord Voldemort takes his rightful place in the wizarding world…." He paused and listened. "Shush, here they come…." He pointed a long, pale finger at the marble staircase.
Snape looked expectantly at the staircase and saw a strange group approaching through the small corridor that was a shortcut from the Astronomy Tower. A tall young man with red hair walked at a brisk pace; two figures, gagged and bound, floated in the air ahead of him.
"Weasley?" Snape asked incredulously.
"Yes, Ronald Weasley," Voldemort said in a soft voice. "He will be the newest member of our family. And he brought a gift for his master. The greatest gift he could bring. He brought me Harry Potter."
"Yes, Master. I brought you Potter and Granger." Ron Weasley placed the two bound figures in front of Voldemort. He then knelt down briefly to kiss the hem of Voldemort's robes and stepped back respectfully.
"So this is your greatest hour, Weasley? Finally getting the attention you always craved, are you? My, my, aren't you a miserable piece of filth." Snape stood at Voldemort's back, his face twisted into an angry grimace although his posture betrayed defeat.
Voldemort spun around and faced him. "Severus, what is the meaning of this?"
"The meaning of this? You don't know the meaning of this, My Lord?" Snape mock-bowed. "Shouldn't the greatest Dark wizard of all times be a bit faster on the uptake than that? What does it look like?"
"You have been trusted. Trusted beyond reason, as it turns out. My most trusted servant..." Voldemort's teeth were bared and his snake-like features had stiffened into a mask of anger and disbelief. "And yet you were a traitor all along. How dare you betray me… Crucio!" He raised his wand and a red flash was shooting out of its end.
Snape ducked quickly, and smoothly moved away from the group.
"A little bit of Crucio, how original. Once again you try to mask your inadequacies with a theatrical performance. Instead of admitting your mediocrity, you still resort to delusions of grandeur. As if you hadn't been beaten by a mere boy again and again." Snape had started to circle the room, moving away from Voldemort and the three students, slowly approaching the door to the Great Hall
Voldemort turned on the spot and watched every one of Snape's moves, getting angrier by the minute.
"How sick I am of constantly hearing the same old boasting and blustering. All this nonsense about your true family… the purity of blood… you who have no idea what a family is, you who torture and demean your servants for the slightest misconduct, you who can't even get rid of your worst enemies by yourself. No, you need another betrayal, another act of a friend betraying a friend, to take hold of Potter. Don't you find it sickening how history repeats itself?"
Voldemort still stood and listened with a slightly open mouth, anger and surprise chasing each other over his features. Anger took over and he raised his wand again. "Enough of this impertinence. You will not escape me again, Severus. You will die…."
Snape braced himself to duck and evade the Killing Curse, but was surprised by a non-verbal Petrificus Totalis. He swayed on his feet and was lucky not to fall on his back. He stood there like a statue, and his wand fell from his stiff fingers.
'So this is it,' Snape thought. The world around him seemed to slow down. From the corner of his eyes, he saw how Voldemort stepped forward and opened his mouth to hurl the Killing Curse at him. At the same time, Hermione Granger stared at him with worried eyes while Harry Potter was still struggling with his bonds. Ron Weasley, who had freed his friends as soon as Voldemort turned his back on them, stood crouched and alert at Potter's back, his wand raised. Hermione Granger hissed, "Harry, now!" but Snape knew that it was too late. The brown eyes of Hermione Granger would be the last thing he would ever see. And then he heard it coming.
"Avada Kedavraaaaaaaaa…" But instead of a rushing wind, Snape heard a howl and, at the periphery of his range of vision, saw his former master flailing wildly. Voldemort had one foot raised like an ice skater, and was skittering over the ground on something slippery, before he crashed to the floor with a loud 'thump', arms still flailing angrily. A heartbeat later, the green flash of the curse that had hit the ceiling and ricocheted back again, hit Voldemort right in the chest. The flailing stopped.
Snape desperately wanted to blink. The three students had watched what happened goggle-eyed, and now cautiously approached Voldemort's body. He didn't move. He didn't breathe. He was dead. At least it looked that way.
While Hermione walked over to Snape and released him from the Petrificus, Harry performed a series of spells over Voldemort. They were ancient and obscure spells that confirmed that the wizard who once was Tom Riddle was truly and finally dead.
Snape looked on in shocked wonder and disbelief. The fear-induced adrenaline had stopped flowing, and he started to shake so much that he had to sit down.
When he finally looked up from the body, Harry Potter, of all people, smiled at Snape. "It's done, he's dead, and I didn't have to become a murderer."
Snape returned the smile with a smirk. "Voldemort always believed in taking matters into his own hands…."
The three friends burst out in laughter. Ron had bent down to look at Voldemort's feet and picked something up. He held it up for all to see and then handed it to Snape.
"Meet the saviour of the wizarding world: the common flobberworm!"
Snape took the dying worm and looked at it thoughtfully. "How very appropriate. The Dark Lord always preferred his servants reduced to cringing worms, only fit to be stepped on."
The three students and their former teacher dissolved in helpless laughter. "I think we will have to found the Order of the Flobberworm when this is all over," Harry snorted. It took a while until they calmed down and the reality of what had just happened started to sink in.
"That was very close, sir." Hermione said, looking at Snape earnestly.
"I've faced death many times, but never been that close," he admitted, getting to his feet and staring down at Voldemort, the dead flobberworm still in his hand. "And to think that I have to thank Neville Longbottom for my life, of all people…."
With another fit of laughter, they finally opened the doors to the Great Hall, where an army of Aurors and Order members waited for them anxiously. They had taken care of the invading Death Eaters while Snape and Ron were leading Voldemort into the trap.
Harry stood by his word and used the money he had inherited from Sirius Black to found the Order of the Flobberworm. Neville Longbottom became an honorary chairman, and Snape was the first to be awarded the Flobberworm Medal of Bravery.