Prologue: Long Shadows Under Falling Stars
Night crept slow on Sakyo city. In a tiny house that shook with every metro rumble, junior high student Minako Ishida bent over an old map. Ink trails ran broken between fields where towers now reached up, fighting the dark. The legend in white said: “Lumerian Ruins. Do not dig.”
Minako traced the borders. Her eyes burned bright. “No one believes there’s anything under here but trash and flood tunnels,” she muttered, “but that’s where the best secrets are.” Why do people turn away from stories of lost worlds? If you could ask, would you?
Act 1: The Mandate From Below
Next day’s history club had three people. Kenta clasped his hands like he wanted to shut out questions. Ayumi just nodded. “You know it could be real,” Minako whispered. “The law forbids digging is what makes it true.”
Ayumi looked up, silent. Kenta frowned: “My granddad talked about a marble pillar under Sakura Waterworks. But his friends laughed at that, Minako! You wanna go ghost-hunting or digging pipes?”
With that, Minako’s mind was set. Something made her room shake that night— water gurgled in pipes, turning slow and cold. Was it a warning or a sign for her to keep searching?
Act 2: The First Descent
Sunday rain left puddles across side roads. Ayumi’s umbrella rattled under weak light as the group found the branch tunnel Minako marked in red. “It’s locked?” asked Kenta, testing rusted bolts with Turkish delight-stained fingers. “But not shut too well,” Minako grinned, snapping open her dad’s auto wrench.
They slipped inside. Cold, wet air bit quick. Echoes underfoot chirped in short bursts, never matching what anyone said.
After fifty steps, old tiles stopped. Slabs of old white stone joined crushed red earth. An idol’s face—its grin chipped—appeared. Ayumi shivered. “Heard of anything like that in your books?” she asked. Minako shook her head. “But maybe not everything IS in books.”
Act 3: Signs and Wonders
Deeper they crept. Painted walls in spiral marks sloped low, heavy with dust. Every footfall made a new pattern in dry silt. Light caught faces carved so long ago all edges were dull. Why did these people vanish? 
Kenta flicked his headlamp toward strange drips on the wall. “Looks…like writing. Or? Ayumi, can you read it?” She squinted, tracing signs. “Can only guess at shapes. It repeats.”
Minako’s breath hitched when thunder boomed above. “Once more, deeper. Look at that big archway up there.” Each heart in her chest rhymed with another in stone below—always a pair, never alone. Why do we fear empty halls even with friends?
Act 4: Guardians Awaken
The archway led to an open space. Silent for so many years, the room pulsed faint under blue-gray dust. In the center, an orb glowed, levitating above carved hands. “Did you bring this place awake?” hissed Kenta. Minako did not look back.
Ayumi edged closer. “Feels like the time behind time,” she murmured. Crackling lines appeared, moving over that orb’s outer layer. Minako stepped quick. Her palm brushed stone at the altar’s edge. Something inside whispered — or was it the wind lacing shaken pipes? — “Below the world you know, names are keys.”
Kenta’s voice was thin. “Why do they need us now? Why now?” But it was too late—other lights appeared, like edges waiting to step out.
Act 5: Out of Silence
Static lifted off the orb. Darkness at the room’s edge twisted, changed. Faces like water rippled in the shimmer, half disappeared, half formed. “The children who woke,” an old voice sighed, “have you names to pay?”
Ayumi found words first: “Ayumi, I name myself. And these—my friends.” Thin light passed between pillars—gray-blue, copper, lapis. The room seemed to let out a deep, hard breath.
Minako thought, turning the problem in her mind: the arc of lost things, keys and locks, names forgotten. She didn’t step back. “We want to know why you hid, why we break the law just to stand here. Did you want the city’s stories buried?”
Act 6: The Bargain Echoes
An old shadow answered, sharp and wistful at once. “Lost must stay lost unless a gift is given. Children of the concrete sky, do you trade memory or music?”
Kenta shook. “I’ve only got truth, and maybe lunch.” A laugh (dry and low) sounded behind the left pillar.
Ayumi drew her harmonica—the yellow one she never had played where others hear her. Simple notes wound around silence. Notes curled and shaped the dust. How long since anyone made music that echoed these bones?
Act 7: Names Unlocked
The music was enough. The orb pulsed harder, grew shade after glass shade, filling the space with warm and blue light.
Minako felt names—like ripple in a pond—move through her. Chips of memory, tiny, small. “You hid because you lost something too. You need us to remember, don’t you?” she asked.
Above ground, thunder rolled for the second time. Inside, the room—if you looked close—now showed corridors that hadn’t existed ten minutes before. New sign lines marked the old walls.
Would you dare enter and look, not knowing if you could come back?
Act 8: Doorway to the Second City (Cliffhanger)
Kenta let out a held sigh, clutching his bag close. “If behind that door is more ruin… is this a warning or call?” Minako licked her lips.
“Only one way to find out.” Stone slid light. Their path lit by music, the trio left doubt behind and stepped into what waited. Light ate their shadows as the door shut at their backs. 
A whisper in pale blue: “Know the price… or pay unknowing.”
