Kingdom Hearts fic: In the Dark

[mistressofmuses]

This is the fill for AUgust 2023, Prompt #29: Dark AU. It follows immediately from "Through the Glass."

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Pulled through the mirror, Riku is trapped while his doppelganger roams free. The only thing worse than being stuck in the dark and the cold is watching the doppelganger take over his life.

It didn’t hurt. Riku was surprised by that, when his reflection pulled him through the glass. He expected it to, inasmuch as he expected anything in the split second where he realized what was happening. Instead, the immediate impressions he was given were that it was very dark, and it was very cold. Dark that was the utter absence of light; cold that was the utter absence of warmth. More slowly, a third impression began to assert itself: that this felt wrong, in some bone-deep way that he would have struggled to explain.

The reflection, the doppelganger, this other him, was the only thing in the dark with him, somehow visible against the lightless nothingness. It smiled its cruel smile, and looked Riku in the eyes. That just-too-long hair and just-too-tan skin… changed. The hair grew shorter, the skin grew paler. Its eyes looked bluer. Like it was examining him and choosing to shift its appearance to match.

“So much better,” it said in his voice. Then it stepped back.

Riku tried to reach out, to grab hold of it, but his own motions felt sluggish.

It was like a window appeared in the emptiness behind his double, the light shocking in the dark. The doppelganger stepped through. Riku tried desperately to follow, but he couldn’t. It felt like a nightmare, trying to run, yet hardly able to move, as he tried in vain to reach that ‘window.’

The window was Sora’s bathroom mirror. He could see out, if barely, into the bathroom, and a glimpse of the hallway beyond. And there was his doppelganger, standing in front of the sink where Riku had just been maybe mere seconds before. His false reflection turned toward the open door.

Sora stepped into the patch of light spilling from the bathroom into the hall.

“Riku?” He sounded scared. The sound of his voice was quiet, like it was coming from much farther away.

“No! It isn’t me!” Riku tried to scream. If Sora’s voice had sounded artificially distant, that was nothing compared to how weak his own voice was now. He only produced a thin, choked sound, difficult even for him to hear.

“Sora,” his own voice answered from the thing outside the mirror. “It’s me.”

“I thought I… heard something.” Sora’s eyes flicked to the mirror, but there was no sign he saw anything out of the ordinary.

“Me too,” the doppelganger said. “But there’s nothing there. Nothing to worry about.”

Riku wanted to reach the mirror, to beat his fists against the glass and scream for Sora to run, to watch out, to something, but no matter how hard he tried, he couldn’t reach it.

“Well, that’s good,” Sora said, looking again to the mirror. “Come on then. If you’re tired, you can go back to bed. I can stay up until it’s Kairi’s turn.”

Sora turned around, and the doppelganger followed him.

“Don’t worry, Sora.” Then it turned to look over its shoulder at the mirror. At Riku. “I feel just fine.”

Its eyes may have shifted to better match his blue, but in the bathroom light, they still glinted gold, the only thing that marked any physical difference.

As the doppelganger stepped around the corner out of sight, the window of light vanished, leaving Riku alone in the dark.

---

Riku slowly learned the rules of the nowhere space he’d been brought to. Or he tried to. He was both hungry and thirsty, but not past the point of mild discomfort; he doubted he was going to starve. Sound remained as difficult to produce as it had when he’d screamed for Sora to hear him. The best he could hope for was a thin, strangled sound. Kicking at the “ground” beneath his feet produced no discernible sound either, despite it feeling solid, though perhaps that was related to how difficult it was to move. He could move, but he couldn’t seem to do so rapidly or well. With no anchor or point of reference within the nothingness, it was hard to tell if he was able to travel any distance at all, even when he tried to run. Given his struggle to even approach the “window” the doppelganger had vanished through, he doubted it.

The windows were the best and by far the worst thing.

There was nothing in the dark with him, until one of those windows would appear. Always just too far away for him to reach, but close enough for him to see out of.

As far as he could tell, they appeared when his doppelganger stepped in front of something reflective. Mirrors, but also sometimes windows, or water. Not often enough to be every time it cast a reflection, though it was a mystery as to why some things showed and others didn’t. Maybe the doppelganger could control it. Or maybe it was something else.

They gave Riku glimpses of what it was doing, out in the world. It had returned to his apartment at one point. Then it came back to Sora’s. Once he watched a whole car ride through the side mirror of Kairi’s car as she gave it a ride somewhere. He couldn’t see her from the angle the mirror was at, but he could hear her faintly, talking about the normal, inconsequential pieces of a day.

“I’ll be at the library later. If you need a ride after you’re done, just text me, okay? Or Sora, I’m sure he could pick you up…”

Riku wanted to listen forever, and he wanted to scream at her that she wasn’t talking to him, please please realize that this wasn’t him.

The creature addressed him, once. Leaning on the sink, staring into the bathroom mirror in Riku’s own apartment. Riku of course lunged, though it was still useless, like moving through clay. Unlike when Sora had looked in the mirror, the doppelganger was able to see him.

“Make peace with it,” it said. “Don’t fight me, and maybe I’ll keep showing them to you. You’d prefer that, wouldn’t you? At least a chance to see the two of them, to know they’re okay?”

Riku snarled silently at the thing, though obviously it didn’t care.

“No? You don’t like that? So… would it be better for me to lash out at them? To push them away? If you don’t want them to interact with me, perhaps it would be better for me to make sure they want nothing to do with me. Of course, they believe I’m you.”

“Or…” it said, after a poisonous pause. “I could hurt them, you know. And they’ll still believe it’s you.”

Riku screamed helplessly at it until his throat hurt. It just turned and walked away, and the window disappeared.

---

The idea that the doppelganger could try to destroy his life haunted him. Even if it didn’t seem to be doing anything at the moment, the threat was ever-present. He hoped that if his double said something cruel to Sora or to Kairi they’d realize it wasn’t him, that he would never… but why would they?

It did sometimes show them to him, and the scenes it allowed him to see looked… normal. Painfully ordinary.

The window of a café, Sora and the doppelganger heading inside. Walking with Kairi down the street, reflected in the windows of parked cars. The open bathroom door in Sora’s apartment showing him walking down the hallway toward his bedroom. From below, in what Riku guessed was a puddle of rainwater, as it approached Kairi’s apartment building.

The three of them in Kairi’s living room, reflected perfectly in the darkened screen of her television. They were eating takeout, seated together on her couch.

“You know,” the doppelganger said, “I appreciate you dealing with me while I was a bit of a mess. You know, seeing things and everything.”

Kairi took another bite, then shrugged. “Nothing to thank us for. Of course we would be there for you. Do things seem… better? No more incidents?”

His double smiled. It looked too sharp, aimed just briefly at the television rather than Kairi or Sora. “No. Feeling great, actually. Never better.”

Sora looked between Kairi and the doppelganger. “That’s good to hear.”

Riku’s heart ached.

---

Then, just as he’d been dreading, the threats began.

At first, Riku couldn’t tell that was what it was, when it walked past the mirror inside the door of Kairi’s apartment. It had often visited one or both of them. But the lights were out, and it was clearly the middle of the night.

That window faded, replaced by it walking through her kitchen, reflected in something sitting on her stove. A pot, maybe. Then the darkened television again, showing it approaching her bedroom. In her bedroom, reflected in her darkened window. She was asleep, and the doppelganger just stood and watched.

Riku shouted for her, the sound as empty and faint as ever. The creature did nothing to her, but the message felt clear: it could.

Sometime later, it visited Sora. It showed Riku fragments of a perfectly ordinary evening. They even had a conversation within view of the bathroom mirror where it had first taken Riku away; the doppelganger asking to stay the night, Sora offering it blankets for the couch. It hovered in the doorway while Sora brushed his teeth. Such a stupid opportunity to see him, and Riku flailed uselessly, wishing Sora could see him through the mirror the way the doppelganger could.

Then Riku was seeing through Sora’s bedroom mirror. Sora asleep in his bed, the doppelganger standing over him, holding a knife from the kitchen. And it looked up at the mirror and grinned, eyes just briefly glinting gold, like an animal in headlights.

Riku screamed, and of course the monster knew it, and just broadened the grin. It held the knife, tilting it back and forth, contemplative. Then it shrugged, and calmly left the room, the window vanishing with it.

Riku collapsed, as much as that could apply in the dark. There was nothing he could do.