They were in virgin territory.

  That was the thought that kept circling—thrilling and dizzying—as the twins pushed deeper into the cave’s depths. No trail markers. No graffiti. No chalk lines or abandoned climbing rope. Just pristine stone and the heady certainty that they were the first foolish or fearless enough to venture this far in.

  Their headlamps bobbed, beams skittering over damp rock. The air grew colder the deeper they moved, heavy and mineral-thick, tasting faintly metallic on the tongue. Every sound felt too loud; every scrape of boot or brush of fabric echoed.

  The passage appeared unexpectedly.

  It was barely wider than their shoulders, a slit in the stone half-hidden behind a curtain of jagged rock. The older twin laughed—breathless and bright—and pushed in. The younger one followed without thinking. They always did.

  The stone closed around them. Progress slowed to inches. Packs snagged. Knees and elbows burned. The ceiling dipped so low they had to turn their heads sideways, cheek pressed to cold rock.

  Their breathing filled the passage; the sound fast and shallow, bouncing back at them until it was impossible to tell whose breath was whose.

  “Just keep going,” one of them said. Or maybe both did.

  It didn’t matter, they were in it together. Where one went, the other followed. They were inseparable and both felt the urge to explore, to go higher, faster, deeper.

  They’d been like this since they were kids.

  One of them preferred controllers and keyboards, fantasy paperbacks stacked beside the bed, worlds mapped neatly in quests and skill trees. The other filled sketchbooks with half-finished faces, left music playing too loud, felt more at ease chasing a feeling than a rule set. They argued about art and logic, intuition and planning, whether it was better to know the map or trust your feet.

  But when it came to the real world, the answer was always the same.

  Together.

  They hiked until their legs shook. Climbed rock faces that scraped their palms raw. Learned to breathe underwater, to fall out of the sky, to balance on narrow edges with nothing but air yawning below. If there was a way to test the limits of a human body, they found it, packed snacks, and went side by side.

  Their mother hated it.

  Every phone call that started with “We’re fine” made her close her eyes and grip the counter. Every return home brought new bruises, new stories that made her turn her back and busy herself with dishes that were already clean. She muttered about ulcers and funerals and how some people only got one child and somehow that was safer.

  Stolen content warning: this tale belongs on Royal Road. Report any occurrences elsewhere.

  Once, half joking and half not, she said she was going to figure out how to bring them back from the dead just so she could kill them properly herself.

  Mom might finally get her chance, one of them thought now, as they struggled to exhale, the stone pressing tight against their ribs.

  For a long moment, terrifying and quiet, the passage narrowed even more. The thought surfaced sharp and identical in both their minds. Trapped.

  Panic fluttered, small but vicious. Muscles trembled. Fingertips scraped raw stone, searching for leverage that wasn’t there.

  Then the rock opened.

  They spilled out of the passage in a clumsy heap, gasping, skin stinging, hearts pounding hard enough to hurt. The space beyond swallowed their light.

  They froze.

  The cavern was enormous. Vast enough that the ceiling vanished into shadow, vast enough that the air itself felt different, lighter somehow. Crystals erupted from the walls and floor in impossible clusters, faceted and smooth, tall as trees or scattered like spilled glass. They glowed softly, just enough that the darkness never quite settled.

  The twins switched off their headlamps without speaking. They didn’t need them.

  At the center of the cavern lay a lake.

  Its surface was perfectly still, black only until they stepped closer. Then it resolved into clarity so complete it felt unreal. They could see the stone sloping down beneath the surface, every ripple of sand, every fallen crystal shard resting untouched.

  Neither of them spoke for a long time.

  They were shaking now, but not from fear. From relief and triumph. From the sheer electric knowledge that they had found something no one else had ever seen. Their exhaustion hit all at once. The heavy and sweet feeling settling into their bones.

  “We should rest,” one of them said. The other was already nodding.

  They dropped their packs. Sat on the cool stone. Laughed quietly at scraped arms and bruised knees. The cavern felt safe. Protective. The crystals hummed just at the edge of hearing, or maybe that was their blood finally slowing.

  The idea of the water crept in gently, then all at once.

  They were hot. Filthy. Every muscle ached. Their stomachs swirled. The lake looked impossibly clean, impossibly inviting. The excitement that bloomed at the thought felt too strong, too sharp, but neither of them questioned it. Nerves, adrenaline, the aftermath of panic. That was all.

  They stripped down to their swimsuits, movements quick and eager. The stone beneath their bare feet was cold enough to make them hiss, then laugh again.

  They stood at the edge of the lake.

  For a heartbeat, something in the back of one twin’s mind whispered that something wasn’t right. The nausea rose. The water was wrong. The thought slipped away before it could take shape.

  They jumped together and ceased to exist.

  * * *

  Somewhere neither here nor there but also everywhere and billions of light years over there, a god spewed scalding hot coffee out of his nose. “Did you see that shit?!”