Severus had always had an instinct for danger, developed as a wary, frightened boy with all the world against him and honed as an angry, remorseful young man playing a dangerous game. This instinct had kept him alive when he should by rights have been dead, warning him of his father’s anger or the Dark Lord’s suspicion, and so he listened to it.

It was already sounding when Albus left on Fudge’s summons and when Quirinus didn’t appear in the staffroom after dinner. When Minerva made an exasperated but cryptic comment about children who thought they were a creditable defence, it howled. Severus strode out of the staffroom, ignoring Minerva’s startled look and almost tripping over Filius, whom he hadn’t seen in his single-minded determination. All his watching, all that he had worked for – had it been in vain?

Something was wrong. Something was very wrong.

---

He stumbled through the flames he had used in his defence of the Philosopher’s Stone, wand in hand, to find Potter and Quirinus struggling urgently in a macabre game of Keep Away. Potter was trying desperately to keep out of reach but at the same time hurt Quirrell, his touch somehow scalding the man’s skin. Quirrell tried to stay out of harm’s way, his cheeks charring and his eyes full of wild tears, but also wanted something from Potter’s pocket badly enough to invite burning. Severus stared a moment at the strange scene, feeling a twinge of annoyance at Potter’s ill-judged presence but satisfaction at having suspected Quirinus all along.

“Get away from him, Potter!” he snapped, raising his wand. Just give him one opening, and Quirinus would be down. The boy tried to obey, but Quirrell caught his sleeve in a remorseless grip, holding him at arm’s length.

“So kind of you to join us, Severus.”

It wasn’t Quirinus who spoke. Severus’s mouth went dry and his grip tightened painfully on his wand. “My – my Lord?”

Potter struggled, clutching at the hand that held him. Quirinus swore viciously and gave the boy a violent cuff, but Potter fought on undeterred.

“Take the boy, Severus. I cannot touch him.”

Severus didn’t understand. How could the Dark Lord be here? Where was he? How had he gotten into the heart of Hogwarts? Potter glared at him defiantly but Severus was moving as if in a dream. “Accio Potter.” The boy flew to him, immediately fighting against Severus’s death-grip on his arms. Severus hardly noticed a sharp kick to his shins, too intent on watching Quirinus turn, seeing the ghostly, ghastly face of the Dark Lord on the back of the man’s head.

“Excellent, Severus.” Red eyes smiled in unholy delight. “He has the stone. Give it to me.”

Once he had loved this man, father-figure and leader to a new and better way of life. This man had betrayed him. “No.”

Potter stopped struggling. Quirrell stiffened in horror.

“No?” the Dark Lord said dangerously. “Have the years destroyed your faith, Severus? Have you forgotten your loyalty?”

“I have forgotten nothing.” None of the pain and humiliation, none of the atrocities – and not the death of his mother for daring to marry a Muggle.

”Kill him!” the Dark Lord ordered, furious, and Quirinus spun gleefully, firing a spell.

Severus pushed Potter aside and fought back. It was the war all over again, fighting for his life, desperately seeking an opening in his opponent’s guard, hoping so very hard that he would win because it was the only option he dared to consider. This was the truth Severus had come to understand: the Dark Lord could only ever offer pain and strife. There was no bright future under his leadership. There was nothing.

“Are you surprised, Severus?” Quirrell demanded, raising a complicated shield. “Did you think I would be easy to defeat?” Severus threw himself to the floor to avoid a flurry of spells. “You always believed I was weak, didn’t you? All of you! Poor little Quirinus with his bad grades and his feeble magic.” The man dodged adroitly and flung back a spell that shattered Severus’ shields. “But I am not weak, and I will help my master—“

He screamed, for Potter had flung himself at him, forcing his hands onto Quirrell’s face, searing his skin. Quirinus flung the boy away with a howl of desperate pain, and Severus took the moment of distraction to bind him tightly. Potter threw himself back at the man, causing Quirrell to fall; the boy held his hands to Quirinus’s cheeks while the teacher writhed helplessly. The boy’s face was set, his eyes tightly closed, his shoulders trembling.

Severus stepped forward. “Potter—“

Quirinus shrieked. Shrieked and shrieked and shrieked as Potter burned him again and again and again until the man was dying while Severus stood uselessly by. The boy slumped over Quirinus's chest, barely keeping contact with his skin, as the Dark Lord’s face faded from the back of Quirrell’s head. As Quirinus’s screams faded away, something dug at Severus’s Dark Mark, pulling at the magic there and following its link up his arm and into his head before he could do more than scratch futilely at his skin. The presence settled into his mind, a force of dark malevolence unimpeded by his Occlumency walls.

“Well, well,” the Dark Lord said. “So it is true after all, my little spy. You will pay for this treachery, Severus.”

From where he bent gasping over Quirinus, Potter pushed himself up, white-faced and exhausted. “Fight him, Professor! Fight him!”

“Oh, he is, Potter. He is.” The Dark Lord laughed.

Severus forced his unresponsive legs to propel him forward, raging against the hated entity in his mind (his mind! the one thing that was his and no one else’s!) and fighting for control. He stumbled, going to one knee beside Potter, who looked up at him with anguished green eyes.

“Give me the stone,” the Dark Lord ordered.

“Leave him alone!” The boy’s voice wavered; he was exhausted and pushed beyond all limits.

“A bargain, Potter. The stone or your teacher’s life.”

“Potter—" Severus ground out, battling for every movement. “Please—“

The boy hesitated, then moved forward, his hand going to his pocket. “I’m sorry, Professor.” He struck before the Dark Lord could react, reaching up to cup Severus’ face almost tenderly, and Severus welcomed the pain, welcomed the Dark Lord’s savage fear. He clung to his former master’s soul, feeling its strength ebbing, determined that if he must die he would take the monster with him. But his grip slipped and weakened as he burnt under Potter’s small, steady hands, and the Dark Lord was flung free – into Potter.

“No!” Severus gasped, fighting to pull himself up.

They screamed together, the Dark Lord and the boy, screaming as though neither could bear the other, as though each other’s presence was the Cruciatus thrice over.

“Let me go, Potter!” the Dark Lord shrieked, voice laden with fear and pain and horror.

“No!”

“We’ll both die.”

The boy gritted his teeth. “Don’t. Care.”

Voldemort screamed.

---

It was Albus who found them, naturally; Albus who found his way into the Erised chamber, Albus who found Severus with burnt, cracking skin and a pale, still boy cradled in his arms.

Albus, who was the first to learn that the Boy Who Lived lived no more.

Severus told him, every word tearing at his burnt cheeks and making them bleed as he ran his long fingers through the boy’s tangled hair, feeling the smooth, freakish face of the Dark Lord on the back of the boy’s head.

Albus, who wept.

---

There was a funeral, naturally, full of crying, grieving people. A closed casket, that no one might see the dead Dark Lord forever trapped on the back of a small boy’s skull. And Severus, tall and grim in the midst of the mourners. What right had they to weep? Only the students and teachers had known the boy; what right had these others to pretend that they somehow cared?

They didn’t even know him.

Not like Severus, stiff and unmoved as Minerva sobbed into his shoulder. Not like Severus, calm and untouched in the centre of futile emotion. Not like Severus, who knew anguished green eyes and a boy who defiantly chose death.

In the row in front, the youngest Weasley boy tried to jump up, full of angry, helpless tears, but Severus held him down. “No, Mr Weasley.”

Hating, angry eyes glinted at him. (“Why was it him? why didn’t you die?”) Did the boy think he had a monopoly on pain? “But – Malfoy—“

“Not here. Not when Miss Granger needs you.” The boy turned back to his friend and Severus closed his eyes a moment in something that was almost relief.

There were speeches. Proud, empty words of courage and resolution. Not the boy with too much defiance and messy writing, who was too lazy to do as well at his schoolwork as he could have done. Accolades of heroism and greatness. Not the boy who earned detentions and snuck about the school at night when he should have been in bed.

Still and cold in the midst of unrestrained grief, Severus remembered angry green eyes and insolence, and sitting on a cold stone floor with a fragile, broken body in his arms. A boy. Not a hero. Just a boy.

He wore green for mourning, the colour of a dead boy’s eyes.

---

They were heroes now, the boy and the spy who together had fought and defeated the Dark Lord. It should have been Potter, Severus told them it should have been Potter, but they wanted a living hero as well as their martyr. He stopped fighting them eventually; stopped speaking except to lecture a class. He wasn’t a hero. He didn’t want to be a hero.

He sat at the teacher’s table at the Leaving Feast, ignoring the black and maroon and gold of mourning and celebration, ignoring the stares and the whispers, ignoring the concerned glances of his colleagues. He stabbed absently at his food and watched the pair at the Gryffindor table which had so recently been a trio.

He wanted Potter back. He wanted Potter to take the adulation for his foolishness, he wanted Potter to take the attention from him, he wanted Potter to be the hero so that he could go back to his comfortable obscurity. He wanted Potter back so that he could ask why an eleven-year-old boy had been so unafraid to die. So he could ask why the boy’s relatives had said “Good riddance” when they were told he was dead. So he could ask why only wizards came to the boy’s funeral.

So he could ask the questions he would never dare to voice to anyone else: Why did you take him from me? Why didn’t you let me kill him? Why did you die for me?