Remus Lupin was angry. Furious. Enraged. Spitting mad. Fit to breath fire. He was angrier than he had been in a long time; since the overwhelming, all-encompassing grief of Lily and James's death had given way to insurmountable rage: at Voldemort for their murder, at Sirius for his betrayal, at Dumbledore for failing to protect them, at his friends for leaving him, at himself… Yes, this anger was enough to rival even that. Remus Lupin was on a warpath and he was headed straight for Severus Snape.
Remus burst into the staff room, slamming the door open with a thunderous crash. Several people cried out in shock, but Remus ignored them, his gaze cold as solid ice as he scanned the room for his target. He saw a flash of black and a head of greasy hair.
"You!"
He was too angry to even draw his wand, instead shoving Snape up against the wall with his hands fisted in the man's black robes.
"Mister Lupin!" Minerva cried, stepping forward, but Remus snarled and she stopped in her place.
Snape's eyes were blown wide with surprise and the vicious part, the wolf part, of Remus was proud to see, fear. Snape tried to draw his wand but before he could even raise it Remus had ripped it from his hands and thrown it over his shoulder, barely stopping himself from snapping it in half.
"You," Remus growled again, shaking Snape a bit. "You absolute bastard. Sixteen years and you haven't grown up at all. You're still the same miserable piece of piece of shit that you were in school." Remus wasn't much disposed to swearing, but for this he would make an exception.
"I have absolutely no idea what you're talking about, Lupin," Snape said. He had managed to piece together his usual facade of aloofness and superiority. Even dangling by the front of his robes, Snape managed to sneer down his long nose at Remus like he was an insect waiting to be squashed.
"Perhaps," Minerva said, and her voice had that iron-like quality that Remus had become very familiar with in his school days. "You should put Professor Snape down and explain yourself, Professor Lupin." It was clear from her tone of voice that she was not going to be ignored again. Still, Remus hesitated before dropping Snape roughly and taking half a step back.
"I've just come from teaching the third years. They faced boggarts today," Remas spat.
"So?" Snape drawled as he straightened his robes and Remus longed to reach out and wring his neck.
"So, imagine my surprise when the first student steps up to face their worst nightmare, the thing that scares them most in the world, and out crawls you, their professor."
There are gasps all around the room. A smattering of muttering. Out of the corner of his eye, Remus sees Minerva pale.
Snape however, looks utterly unconcerned.
"Which student is this?" Snape inquires coolly.
"What does it matter?" Remus snarls. The fact that any student, any child, would have to face a boggart in the form of their teacher is abhorrent.
"Which student, Remus?" Minerva asks and she sounds a little breathless.
Remus hesitates. He doesn't want to invade the boy's privacy, but, then again, half of the third year class had seen the Snape-boggart. The story would be all over the school within hours regardless of what Remus revealed here.
"Neville Longbottom."
Snape's indifferent expression doesn't falter except for the tiny hint of a smirk tugging at the edge of his lips.
And Remus is furious all over again.
"You asshole," Remus hisses and shoves Snape back against the wall once more. "You're his teacher! You swore upon accepting your position here that you would protect the children in your care! They're supposed to trust you! And you laugh at the idea that you are this child's worst fear? Not failure! Not rejection! Not ghosts or beasts or even goddamn Bellatrix Lestrange, who robbed this boy of his parents and sentenced them to a fate worse than death! God, if there's anyone that boy should fear, it's her! But it's not! It's you! For all you condemn James of for being a bully in school, you are certainly no better as a grown man! At least James grew up! You're still the same pathetic little gremlin you always were. Damn you, you utter bastard!"
His words echo around the room and a thick, oppressive silence reigns. No one member of staff witnessing this altercation dares to interrupt. Snape seems to struggle to form coherent thoughts. Finally, after several minutes of suffocating silence, Snape speaks.
"I wonder," he says, and his voice manages to sound both like silk and like slime, "how many students would fear you, if they knew what you really are."
Remus eyes flash dangerously. It's a threat. He knows it is. He had expected this. He had expected Snape to try to turn this around using what he knew was Remus's biggest weak spot. He's done it before: spun Remus's own self hatred into wicked barbed weapons aimed to kill. But this time, Remus is prepared. Pulling back his lips into a vicious snarl and leaning in until his was mere inches from Snape's face, Remus let the shadow of his wolf come to the surface.
Snape must notice the change in his eyes because he suddenly cringes back and swallows nervously.
"What I am," Remus hisses, and his voice is so low that only Snape could hear, "as far as they know, is human. Just as human you. And they don't fear me at all. But you're Longbottom's boggart, so I wonder, Severus, which of us is the bigger monster?"
Snape hardly dares breath. Remus allows his wolf to relish in his opponent's fear for a moment before he takes a step back and pulls the wolf back down.
"Stay away from Neville Longbottom, Severus Snape." Remus warns him.
"Or what?" Snape snaps.
Remus smiles.
"That is the question."
And with that, Remus lets his persona of mild-mannered scholar fall back into place, turns on his heel, and walks out, silently reviling in the look of utter shock and fear that is etched across Severus Snape's face.