Chapter Text
Severus grunted, annoyed just on principle. It wasn’t that he was being inconvenienced – not at all, really, but it still bothered him when the headmistress had Potter over. It wasn’t even him – he hated all reminders of the past, the war, the before.
All of them. His left forearm twinged and he hissed in annoyance. Potter. His arm always hurt when he thought about the brat – though he was near thirty now, he could admit without too much care. What that meant for his own age – well, he wasn’t fifty yet, and that was good enough for him.
A rap on the door had him jumping from his armchair, the hairs on his arms standing up in instinctive caution. Not fear – it wasn’t bad enough for that, but he could sense that whatever was on the other side of his door wasn’t quite right.
Wand drawn, he placed down his whiskey glass and stepped over towards the door. There was no evil or dark magic being cast – yet still, there was something out there. He cautiously opened the door – and came face to face with a familiar if terribly unwelcome smile and bright green eyes.
“Good evening, Professor. May I come in?” Potter asked, smiling.
It was terribly ill-fitting to the creepy sensation of danger that kept inching across his body.
“No.” He said instinctively.
Potter looked surprised – then he smiled. “Might be for the best. I need a favour. Massive, life-changing, life-debt-erasing sort of favour.” He said bluntly, his smile fading at the edges. Severus gripped the door a little more tightly – he did not care for the reminders of what he owed the brat – the master of death – for dragging him back to life with his blasted Hallows, thank you very much.
So far, Potter hadn’t ever mentioned it, not in the decade-plus since the war.
“We should speak, in private.” Potter said.
Severus squinted at him. “My office then.” He hissed, before slamming the door shut.
Whatever it was – whatever Potter wanted – it would not be happening in his rooms.
“Speak.” He snarled at the younger man when they were both sitting in his office. Potter’s smile was gone – replaced, now, by an almost parody of it, a curl of his lips. He looked tired.
“I need help. Desperately. And it’s… it’s a massive issue. I’ve no idea where to even begin.” He admitted.
“A given.” Severus snarled angrily – Potter didn’t even acknowledge it. He leaned forward – the brat had always been quick to rise to such things before. “What is it?”
Potter sighed. “You know. You sensed it. Which is – well, remarkable, really. Nobody else has, so far. Not anybody.”
Severus stiffened – so his senses hadn’t dulled, then – not that he’d thought they would have. He quickly thought back – a dark presence. ‘Might be for the best’ Potter had said.
“Merlin, you…” He felt a little faint, crossing the line from cautious to scared. If he was right…
“Unfortunately. Sorry, Professor.” Potter confirmed. “Happened about five months ago. I thought I could cope, but my job.”
“How many have you killed?” He asked bluntly.
Potter flinched, his expression crumpling into something else entirely. “None. Nobody. Not… like that. Killed a dark wizard with a spell, that’s all.”
He laughed harshly. “You expect me to believe…”
“I’m not lying. I need your help, it would do me no good.” Potter said.
He gnashed his teeth together. “Still, a freshly turned vampire…”
“I woke up turned in an abandoned manor. Killed a lot of wildlife before I… before I got control of myself. Spent almost two weeks in the woods.” The young man recounted, staring into the middle distance. “Nearly drove myself mad.”
“Animal blood doesn’t work.” Severus confirmed with a nod, suppressing a shiver.
“It does not.”
“How do you feed?”
Potter smiled mirthlessly. “Seen anything about my prolific love life in the Prophet?”
He wanted to say no – but he had, it was everywhere. He grunted his assent.
“I take them home. Obliviate them. Gotten real good at brewing blood replenishers and nourishing potions by now.” Potter said with a sour look.
“Merlin save us all. And you haven’t killed anyone?”
“Only by spell. I give you my word.” Potter said.
Severus… believed him.
“And the favour?” He asked. “The life-debt erasing favour?”
“A life for a life.” Potter replied evenly, not looking at him. The man crossed his arms and shivered, although Severus knew that he couldn’t feel the cold.
“You want me to…”
“I want you to cure me – or I want you to kill me.” Potter said quietly.
Severus hissed in shock. “You…”
“I can’t live like this. I’m sure… I’m sure you understand. I only eat as much as I need to survive. Never enough to feel full – and every time I go into the sun it drains me. Only so many nightshifts I can take.” Potter said, rubbing his hands over his eyes. “I can feel the thing that would ease my hunger in the veins of everyone around me. Do you know how good vampiric hearing is? I can hear your heart race, speeding up by the minute.” Potter said.
Severus sneered, embarrassed that the other man could tell – he was trying not to be afraid, but he was sat in close proximity to a creature who would have no issue dispatching him if it so chose – a man who had little reason not to, in the first place.
“There is no cure.” He said carefully.
“No, but there are books, and you’re brilliant. I want you to find a cure. Make one. Whatever it takes. All the money I have in Gringotts. All the favours anyone owes me.” Potter said with a weary sigh. “Or death, if it doesn’t work.”
“You want me to kill you?” He asked with a shudder. For what it was worth – that, at least, he found as distasteful as Potter ripping him to shreds. “I spent my entire life keeping you alive.”
“Yes.” Potter agreed. “I know. You must be right sick of it. An Unbreakable vow, that’s what I want. That you will either cure me or kill me. The Vow will serve as payment for the life debt. I know you feel it.”
He did, damn the brat. Not constantly, but it was there when he thought of Potter – and he did so far more often than he cared for, than any sane person would.
He swallowed thickly. “That oath…”
“I will insist. I’m quite serious, Professor – I cannot, will not live like this.”
“Why not kill yourself?” He asked, uncaring how cold-hearted he sounded.
Potter didn’t take offense. “Because I don’t know who else owes me life debts. Who else might be… dragged down with me. How magic might collect the debts. They’re not – they’re not two-way streets.” Potter said with a shudder. “I know… I know of a few. That people owe. Lesser than yours, certainly, and I wouldn’t want to harm any of them.”
“But if you were killed by the fulfillment of a life debt…” He theorised, wondering how Potter had gotten the idea.
“It’s the safest way, I should think. The best way I could think of… and I’ve been thinking about it since the minute I understood what I was – am.” Potter said. “Nearly half a year. Can you imagine what it’s like?”
“No.” He admitted truthfully as he stood. “I will swear your vow. Owing a life debt to a half-living creature might be the only thing worse than owing it to the blasted saviour of the wizarding world.” He snarled.
Once again, Potter didn’t take offense – he laughed softly. “I’ll say. How unlucky you owe it to both.”
Sneering, hating Potter like he never had before, he held out his arm. Potter watched him and studied him for a moment before taking his hand – his touch was cool, firm without being unpleasant… but now that Severus knew, a cold shudder ran down his back.
“Swear it.” Potter ordered softly.