Oath of the Devil's Sea —In the Shadow of the Star-Bearer—
Aira, the sea witch who rules the underwater kingdom, dreamed of reclaiming the surface world with her people. They are the proud descendants of a race sunk into the abyss by humans. Aira believes it is her mission to guide the surface toward 'true order' through wisdom and conviction, not just hatred.
But standing in her way is the radiant songstress, Serafina, who beguiles the people with her pure smile and magical voice. Serafina heals the coastal kingdom with her songs, unintentionally crus
Oath of the Devil's Sea —In the Shadow of the Star-Bearer— - Requiem Hymn —The Night the Whirlpool and Tentacles Devour the Harbor
The full moon of the mid-autumn festival cast its cold light over the port of Petralca.
The moon hung in the cloudless night sky, unnaturally large, its pale glow throwing shadows across the stone-paved wharf. On any other night, the dockworkers would have gathered in the taverns by the time darkness fell, but tonight they were likely in their own homes, tilting cups for moon-viewing—the port was sparsely peopled. The smell of the tide and the scent of the preservative oil used on ship bottoms hung stagnant in the windless night air.
Seven fishing boats lay moored in the harbor. Prepared for the great spring tide of the full moon, their carefully secured hulls floated as black silhouettes on the calm water.
On the deck of one of them—the *Kaienmaru*—the old fisherman Gregorio stood alone, gazing up at the moon.
It had been nearly a month since the sea had taken his son. The old man who had collapsed weeping at the tip of the breakwater that morning still could not bring himself to leave the sea. The ebb and flow of the tide was the only clock his life had ever known. His wrinkled hands rested on the gunwale, trembling faintly.
Without warning—
The sea's surface began to move strangely.
Though there were no waves and no wind, the water at the harbor entrance began to slowly recede. As if some enormous mouth had opened at the bottom of the sea and was drawing the tide into itself. Gregorio furrowed his brow and leaned out over the gunwale.
"…What in the world is that?"
His voice reached no one, vanishing into the strangely hushed night sky.
Three kilometers offshore, beneath the sea.
In the darkness fifty meters down, where moonlight could not reach, Queen Aira had begun her incantation—alone.
Her long, silver-blue hair glowed faintly, swaying and rippling independent of the water's movement. Her amber eyes were closed, her sharp fingertips forming a seal before her chest. Around her, a space roughly three meters in diameter was isolated from the water pressure, the silence of the deep sea maintaining perfect stillness.
At her feet, the veins of lumina crystal that covered the seabed pulsed with a pale white light. A nexus point of the crystal veins spreading through the waters off Petralca—if she channeled magical power through this single point, she could seize control of the currents throughout the entire port.
Aira began to sing.
The first sound was not so much a voice as a low-frequency vibration that shook the sea itself. There was no melody. Only a sequence of ancient Meridian words that composed the spell formula. A cold, emotionless, purely calculated song. The lumina crystal resonated, its pulsation spreading across the seabed in ripples.
(*Tonight—*)
Deep within her heart, eight hundred years of hatred burned quietly.
(*Tonight, I will return that port—that symbol of surface-dweller arrogance—to the sea.*)
The Great Exile. The night thirty thousand of her fifty thousand people died. The memory of fire and blood, her grandmother clutching her as they fled. That day, the surface-dwellers had called the Meridian people "a threat of the sea" and cut them down—women and children alike. The shell pendant swayed gently in the current.
Aira's song began to change.
The mechanical sequence of the spell incantation gradually took on emotion. Hatred, sorrow, eight hundred years of solitude—they distorted the melody. The magical power that should have been under perfect control swelled beyond her will.
The seabed rumbled.
At the harbor entrance, the receding tide stopped.
And then—the water's surface rose, unnaturally.
At first it was a small whirlpool, perhaps ten meters across. But within seconds it expanded at an accelerating rate—fifty meters, a hundred, two hundred—engulfing the harbor entrance. Countless bubbles surged up from the seabed, the seawater churned violently, and a deep, rumbling bass note shook the stone paving of the wharf.
"Hey, what's that?!"
"A whirlpool! A whirlpool's forming!"
The night watchmen on the breakwater shouted. One of them struck a bell, and the alarm echoed through the harbor. Fishermen who burst out of the taverns froze as they looked at the sea.
Five hundred meters across.
The center of the churning spiral was dark as pitch-black void, continuing to swallow the seawater.
Beneath Gregorio's feet, the *Kaienmaru* groaned. The sound of mooring ropes snapping. The hull tilted and began to slide slowly toward the whirlpool.
"Gregorio! Run!"
Someone's shout. But the old man could not move. Before his eyes, the whirlpool opened its mouth, and his boat, his comrades' boats, were swallowed into the sea, spinning like leaves.
The first boat vanished.
The screams of its three crewmen rose into the night sky, only to be drowned out by the roar of the whirlpool. The second boat. The third. One after another, moorings snapped, and fishing boats were dragged into the spiral. The men left on deck were hurled into the sea, slammed against the edge of the whirlpool, and disappeared beneath the water.
"Uwaaaaaah!!"
"Help us!!"
A scene of utter chaos and despair. As the dockworkers fled in panic toward the high ground, one man ran against the tide of the crowd.
The merchant Carlo Medina—Carlo, disguised as a black-haired human through transformation magic—had been on his way back to his inn after a meeting with a trading partner. The moment he witnessed the whirlpool's birth, he felt the core of his body freeze.
(*Lady Aira…*)
This was the queen's power. The falsehood in his report—"not a threat"—had brought about this catastrophe. At the edge of his vision, an old man tripped and fell.
Carlo's body moved on its own.
"Get up!"
He grabbed the old man's arm and pulled him to his feet. It was not the action of someone whose duty was to stand by and observe. But the memory of someone who had reached out a hand to him as a child, buried under rubble in a mine collapse, drove his body forward.
Two more children, nearly crushed beneath a collapsed cart, were crying. Carlo hoisted both onto his shoulders and ran for the high ground. Behind him, something shattered with a thunderous roar.
He turned to look—
The sea's surface had split open.
A kraken, thirty meters from end to end, had risen from the deep. Its enormous dark-purple body kicked up waves as its eight tentacles stretched into the night sky. Each one was as thick as a grown man's torso, and countless suckers glistened wetly in the moonlight.
A tentacle came crashing down.
The stonework of the breakwater was blown apart like paper. Hundred-kilogram blocks of stone fell into the sea, sending up pillars of water. Another strike. The quay wall shattered at its base, and the remaining moored fishing boats capsized from the impact.
"H-hiii…!"
A fisherman who had failed to escape was caught in the collapse of the quay and thrown into the sea. The whirlpool seized his body and dragged him under in the blink of an eye. He desperately thrashed his arms, but the power of the spiral cared nothing for a human's swimming ability.
The fisherman vanished into the whirlpool.
Carlo's fists trembled.
With his transformation magic, he could temporarily manifest the powers of the Meridian people. Underwater breathing and enhanced physical ability. If he released it now, he might be able to save that man. But—if he dispelled the magic, his human disguise would fall away.
Thirty years of infiltration work would come to nothing.
(*Can I…*)
His hesitation created a momentary opening.
Through that opening, a figure in white robes ran toward the breakwater.
—Serafina.
From the moment she became aware of the chaos in the harbor, she had been running against the fleeing crowd, toward the tip of the breakwater.
There was no calculation.
She had simply seen someone's arm reaching up from the water's surface at the center of the whirlpool. That alone had set her body in motion. Breathless, heedless of the hem of her nightgown tearing, she dashed up onto the crumbling breakwater.
"Serafina! It's dangerous, come back!"
Someone's attempt to stop her never reached her ears.
A kraken's tentacle smashed the stone paving right before her eyes. Fragments grazed her cheek, drawing a line of blood. The tip of the breakwater was now barely a meter wide. One side had collapsed, shearing off sharply into the sea. The briny wind lashed at her, and spray stole her vision.
Still, she did not stop.
She gripped the iron post of a broken railing with her left hand and clutched a small fragment of lumina crystal in her right.
Beneath the sea, Aira's amber eyes opened.
Through the lumina crystal veins on the seabed, she could perceive the state of the harbor as clearly as if she were holding it in her hand. The kraken's tentacles destroying the breakwater, the terror of the humans who had failed to escape—all of it reached her as shifts in water pressure.
(*Yes… more.*)
Her lips twisted faintly.
(*Carve your terror into this sea. The despair we felt eight hundred years ago—*)
But at the edge of her consciousness as she continued her incantation, a single dissonance caught.
At the tip of the breakwater, there was a human presence.
Not fleeing. Not frozen in place. About to begin something. Aira furrowed her brow and focused her awareness on that presence.
Serafina drew a breath.
She filled her lungs with the sea breeze and wrung her voice from the very depths of her body.
—The Requiem Hymn.
A melody originally meant for funerals, to return the souls of the dead to the deep sea. A song of healing and farewell, passed down through generations from her mother, her grandmother. The fragment of lumina crystal began to glow warmly in her hand.
"La—"
The first note was released.
Her voice cut through the wind, pierced the waves, and was drawn into the heart of the whirlpool. Her pale golden curls began to glow in the moonlight. Deep in her throat, the power of the lumina crystal resonated with the song, and light enveloped her entire body.
The whirlpool wavered, ever so slightly.
On the seabed, Aira's eyes widened.
(*This song—*)
Song magic that used no lumina crystal as a medium. The *Songstress of Light*—one born only once every several hundred years. The very girl she had ordered eliminated.
Why was she here?
Why was she standing?
What had Carlo been doing?
Aira's thoughts spun furiously even as she maintained her incantation. But more than that, a dissonance that seemed to scrape against her entire being ran through her.
Serafina's song was not a weapon.
It did not destroy the whirlpool. It did not attack the kraken. It was simply a melody to soothe the dead and calm the sea. No calculation. No hostility. Nothing.
And precisely because of that—it shook Aira's incantation of hatred at its very foundation.
(*Stop.*)
Aira clenched her teeth and intensified the power of her incantation. The whirlpool grew even more violent, and the kraken roared, flailing its tentacles.
At the tip of the breakwater, Serafina's body swayed.
A kraken's tentacle grazed the stone paving right beside where she stood. The impact crumbled the footing beneath her, but she clung to the iron post and continued to sing. Her throat burned. Her vocal cords screamed, pleading their limits.
"…Lu… mi… na—"
The hymn was not even a third of the way through.
Still, she sang.
The taste of iron spread through her mouth. Blood welled up from the back of her throat. She bit down on it and forced her voice out. Her vision blurred, the moon doubling. Spray struck her face, cold saltwater mixing with the blood at the corner of her lips.
(*If my song can help someone, even a little—*)
That was everything to her.
No expectation of reward. No calculation. Knowing the danger of ruining her own throat, she still sang to save others. To her, song was simply that, and nothing more.
In the shadow of the high ground, Carlo watched, breath held tight.
Serafina's voice was beginning to fray. Even from