Harry opened and shut his mouth a few times, but couldn’t find any words. Snape was wiping his shoes on the mat— it said Welcome in thick black letters— and then he was walking into the house past Harry.

Why was the man here ? It didn’t look like he’d come to borrow a cup of sugar… But, but, did Snape know his parents? He must, or why would he be here—

“Harry?” Came his mother’s voice, getting louder as she got nearer. “Harry, who was it— oh, Severus!”

Harry stood frozen, flicking his gaze between his mum and Snape. His mum did know Snape, enough to call him by his first name— and Snape—

Snape was very still, too, for a too-long moment, but then he said, “Lily.” And then he smiled .

“You didn’t say you were coming! But— oh, take that cloak off, it’s sopping.” She strode over to Harry’s potions teacher and somehow divested him of his outer layer, hanging it on a coat-hook. “Come in, we’d just finished dinner— tea? Hot chocolate?”

Then Lily was ushering Snape into the living room, but Harry was still unmoving. He didn’t think he was capable of motion in his shock. But when his mum called out to ask if he was coming or if he wanted to stand in the doorway all night, he found his legs moving.

In the living room, Snape was sitting in an armchair reading the back of the book Lily’s mum had been engrossed in that afternoon. Harry was extremely aware of the man’s presence as he walked in and sat himself as far from his teacher as he could get, on a pouffe. 

“Thank you,” he heard. There was the sound of china mugs being placed on a table.

Then— “Harry, come over here,” his mother said. Slowly, Harry walked over. She pulled him down next to her on the couch, and kept her arm around his shoulder. Harry couldn’t look at Snape— this was too strange, worlds colliding like cold water to the face— so he kept his gaze on the steaming mugs on the table. There was a plate of gingerbread next to them.

“Feeling lonely, Severus?” his mum said cheerily, picking up her mug of tea.

“I need to speak with you about something, Lily,” his potions teacher said. “This is not a social visit. Is your— your husband around?”

Lily waved a hand. “Yes— have some gingerbread, you look half-starved. Harry and I made it this afternoon.”

And Harry watched as Professor Snape picked up one of Harry’s gingerbread men and dipped it in his tea.

“Severus!” said Harry’s dad, walking into the room. “Here’s that book I was telling you about last time we met.” He tossed it over to Snape.

“Hmm,” Snape said, turning it over in his hands. “Thank you.” He put the book beside him then clasped his hands in his lap. “If you would take a seat, please, Mr Potter.”

Harry looked at the man for a second, confused, before he realised that he was referring to his father.

“Mister Potter?” said James. “What’s the occasion?” He sat down on the other side of Lily, and slung his arm around her. “Don’t think you’ve called me that before. Has Lucius Malfoy been hounding you about etiquette or something?”

“No.” Snape picked up his mug of tea again and twisted it in his hands. If Harry hadn’t known better, he would have said the man looked rather uncomfortable. “What do I usually call you, out of interest?”

Lily leaned forward. “Severus, are you well?” she asked, sliding her wand out of her sleeve. 

Snape gave an odd laugh. “Oh, I am perfectly well,” he said. “It is your son who is not.”

“Harry?” Lily asked, confused. “What on earth are you talking about?”

Harry’s dad now had his wand pointed at Snape. “A security question, if you would,” he said. “Forgive me if it is you, but I need to check. Who is Lily’s niece?”

Whipping his head round, Harry stared at his father. A niece ? 

Snape laughed that odd laugh again. “Petunia has only a boy— a boy settled with the lovely name of Dudley, and a personality to suit it. Unless you have a sibling hidden away somewhere there is no niece.”

How did Snape know Aunt Petunia and Dudley?

James lowered his wand. “Severus, are you sure you’re alright?” he asked. “You’re acting awfully strangely. You haven’t had a potions accident, have you?”

The corners of Snape’s mouth curled up in a strange smile. “No,” he said. Then he took his wand out of his sleeve and rolled it across the table to Lily, who picked it up slowly.

“What’s going on, Severus?” she asked. 

Harry thought that was a very good question.

“Oh, nothing much,” Harry’s potions teacher said. “Just the small matter of your son having been absorbed into an enchanted artefact. As I said, this is not a social visit.” He leaned forward and looked Harry straight in the eye. “The Mirror of Erised is nothing to play around with.”

Harry stiffened, suddenly cold. The Mirror — he’d been looking at the mirror at night, under his invisibility cloak— the cloak that Dumbledore had given him for Christmas— but it wasn’t Christmas yet, it was Christmas Eve in a few days, so it hadn’t been Christmas yet—

And he’d just ignored it all, apart from a few concerns that first day, because really this was a dream come true, being with his parents. They had been dead, and it had been the week after Christmas, but then it had been the start of the Christmas hols, and his parents were alive…

“What’s happened?” Harry asked urgently. “ What’s happened? ”

“Yes, Severus,” Lily said, tightening her hand on Harry’s. “What has happened? Harry seems fine to me.”

“How shall I put it?” Snape murmured, eyes still pinning Harry to his seat. “Hmm. Well. You’re imaginary, Lily. And you, Mr Potter. Or do I call you James, here? Strange, that. But in any case, neither of you truly exist. You’ve been dead for ten years.”

Beside him, Harry felt his mother turn to look at James, but he couldn’t stop staring at Snape. A pressure was building behind his eyes; that Snape had walked in and said that was like two different worlds colliding. It couldn’t be true, could it? They were right here, beside him. They had been dead, yes, but now they weren’t and Harry didn’t know why it was like this now, but it wasn’t a bad thing, was it? It was the best thing that had ever happened to him.

“I assure you, we’re alive,” James said. He held out his arm then pinched it, watching the red mark fade away. “I would have noticed if I were a vampire.”

“Really, Severus,” Lily said. “I’m getting quite concerned. Would you come along to St Mungo’s with me? I know you keep saying you’re fine, but—”

“It’s true,” Snape insisted. “I appreciate your concern, and knew it would be hard for you to believe, but it is true. They’re dead, aren’t they, Harry? ”

And Harry burst into tears.