Chapter Text
The Underworld had no sunrise, but when Will Solace stepped into the courtyard of Erebus Palace, it felt like one happened anyway.
The air shimmered faintly around him, a pale golden hue that the shadows didn’t know how to reject. He carried a bundle of dried herbs and what looked suspiciously like… a string of tiny orange gourds.
“No,” Nico said the moment he saw him.
Will blinked in surprise, a sheepish smile gracing his lips. “I haven’t even asked yet.”
“You’re holding pumpkins.”
“Mini-pumpkins,” Will corrected, his eyes glinting playfully. “For decoration.”
“For what?”
“Halloween.”
Nico pinched the bridge of his nose, already feeling a headache coming on. “We’re in the Underworld, Will. Every night is pretty much Halloween.”
But Will only grinned, that maddening mix of sunshine and stubbornness that made gods falter and ghosts whisper. “That’s exactly why we should celebrate. The mortals use it to honor the dead. You know, our neighbors.”
Behind them, a ghost floated by, carrying an armful of spectral lilies, and murmured, “We’d appreciate the thought.”
Nico glared at the ghost. It winked and vanished through the wall.
By midday, Nico found himself outnumbered.
Will had enlisted Persephone, who thought the idea was adorable, and Hecate, whose involvement Nico was still unsure about — he had no idea how Will managed to convince her to join. Even Cerberus had joined in, happily chasing a rolling gourd with his three eager sets of teeth.
By the time Nico surrendered, the courtyard was strung with lights — not mortal candles, but Underworld flames that flickered in shades of orange and violet. Will had even persuaded the shades to form a choir.
“We could have a song,” he said cheerfully while waving a piece of parchment.
“No singing,” Nico retorted immediately. “Last time, the ghosts in Tartarus joined in.”
“That was just one time.”
“And it took three weeks to stop the echoes.”
~✾~~⋇⋆✦⋆⋇~~✾~
The day — or whatever passed for it — moved quickly. Will set up a table of mortal treats: spectral candy corn that shimmered like starlight, pomegranate cupcakes baked with Persephone’s help, and soul-cakes that melted on the tongue, leaving memories of warmth.
Nico didn’t want to admit it, but he caught himself staring more than once.
It wasn’t the food.
It was Will’s joy.
It was the way even death seemed to step back and make room for him.
By evening, the fields of Asphodel were glowing. The spirits had crafted masks — some shaped from bone, others from mist — and danced between the flowers. Charon had shown up uninvited, claiming it was part of the “holiday toll.”
“You don’t even like crowds,” Nico said suspiciously.
“I like income,” Charon replied dryly, shaking his collection jar.
Even Hades made a brief appearance, gaze softening when he saw the courtyard full of light.
“You’ve made the dead remember laughter,” he told Will. “That is no small feat.”
“Just following my boyfriend’s example,” Will said, smiling brightly.
Nico nearly choked on his cider. “You— Will!”
The ghosts giggled. Persephone clapped. Somewhere, a pomegranate tree bloomed out of season.
~✾~~⋇⋆✦⋆⋇~~✾~
When the bell of the River Lethe tolled, the festival began.
The shades glided through the courtyard in slow, dreamlike dances. Will guided a group of children-spirits through a line of makeshift booths — a fortune-teller’s corner (staffed by Hecate’s familiars), a memory-lantern stand, and even a pumpkin-carving table.
“They’re not real pumpkins,” Nico said.
“Nope. Shadowfruit. They hold light better.”
Will’s hands were smeared with ethereal pulp and a grin. Nico found himself carving one too, his blade moving with the precision of someone who could sculpt bone from shadow. He ended up simple — two hollow eyes, a small curve for a smile.
“That one’s you,” Will teased. “Moody but cute.”
“You’re insufferable.”
“You love it.”
And maybe Nico did — in the way you loved something dangerous to admit.
At the edge of the crowd, a few older ghosts whispered.
“Do you feel that?” one of them asked.
“The veil is thinner tonight.”
“Old things are awakening.”
Nico sensed it too—a pulse beneath the laughter, an ancient rhythm that felt older than the Underworld itself. He turned to look, but the shadows merely rippled like water disturbed.
He filed the sensation away, just in case.
~✾~~⋇⋆✦⋆⋇~~✾~
As the festival came to a close, Will found Nico standing at the edge of the Lethe, a small silver lantern in his hands. Inside it flickered a black flame.
"You made one," Will said gently.
Nico didn’t look up. "It’s called a memory lantern."
Will was captivated by the way the black flame reflected in Nico's dark eyes, sensing that Nico was lost in thought about a memory.
"There are old traditions in the mortal world," Nico murmured. "Lanterns are set afloat for souls who have no one left to remember them. The mortals believed the light would guide them home."
Nico carefully placed the lantern on the river's surface, where it floated, casting a shadowy light across the water like sunlight filtered through darkness.
"For Bianca?" Will asked quietly.
"For all of them," Nico replied softly. "The ones we lost. The ones we didn’t save."
Will stood beside him in silence. Then he reached out, brushing his fingers over Nico’s. A second light sparked to life—gold intertwined with black, joining the lantern’s flame.
"For the ones we’ll remember," he said.
The flame burned steadily and grew brighter, as if in agreement.
For a moment, Nico thought he saw them—figures that were half light, half memory: Jason with his calm gaze, Luke giving a faint nod, and Bianca's proud smile.
Then they faded away, leaving only the rippling water of the river and Will’s hand, warm against Nico’s.
~✾~~⋇⋆✦⋆⋇~~✾~
It began with a faint, distant laughter that unsettled anyone who heard.
The pumpkin gourds flickered, and the shadowfruit lights dimmed. The air thickened as something stepped between the layers of the world.
It wore a mask made of bone and leaves, with eyes resembling hollow candles.
“Who summons the Hollow King?” it asked, its voice layered with the weight of centuries.
The shades froze. Persephone stiffened, and even Hecate’s lantern dimmed.
Nico stepped forward before Will could stop him. “No one summoned you.”
“Yet you lit the lights,” the spirit hissed. “You called to the forgotten.”
Will’s glow flared instinctively, warm and defiant. “We were remembering them, not inviting trouble.”
The Hollow King tilted its head. “Remembrance is invitation, little sun. You burn through the dark, and the dark will always come to see who dares.”
Nico’s hand tightened around his sword — a blade of night forged in the Styx. Shadows pooled at his feet, ready.
“If you came for malice, leave. This is our night.”
“Our night,” the spirit echoed, amused. “Shadow prince and sun healer, binding the dark to light. Fitting.”
Its gaze lingered on the lantern floating in the river.
“That flame does not belong to you.”
Nico stepped between it and the water. “Then take it.”
The Hollow King smiled. “A challenge?”
“A choice.”
The air crackled. Will’s hand brushed Nico’s back — not to stop him, but to stand beside him. The shadows behind Nico thickened; the light around Will blazed. When they collided, the world held its breath.
Darkness engulfed the light.
Light pierced through the darkness.
And somewhere in between, they met — steady, defiant, and whole.
The Hollow King staggered back, its cloak unraveling into smoke.
“You cannot prevent the dark from coming,” it whispered.
“We don’t need to,” Will replied. “We just keep it company.”
The spirit’s laughter echoed once more — not cruel, but curious — before it faded, leaving only the scent of autumn leaves and a single black feather.
~✾~~⋇⋆✦⋆⋇~~✾~
The lantern still burned by the river. Will and Nico sat beside it, exhausted but quiet, leaning against each other.
“So,” Will said softly, “does this mean Halloween’s banned forever?”
Nico’s lips twitched. “Maybe just… supervised.”
“Supervised by you?”
“Obviously.”
Will laughed, the sound light and grounding. He reached out, brushing a bit of shadow-ash from Nico’s hair.
“You were amazing,” he said simply.
Nico didn’t respond. He didn’t need to. The faint smile he allowed was enough.
Above them, the twilight of the Underworld shifted, resembling the closest thing it had to dawn. A faint streak of pale gold wove its way through the endless gray. It caught the flame of the lantern, transforming it into a shining blend of sunlight and shadow.
“Happy Halloween,” Will murmured.
“Happy Halloween,” Nico said back, voice softer than the river.
They sat there until the lights dimmed, the ghosts returned to sleep, and the veil settled again.
The lantern burned on.
And for one quiet night, even death remembered warmth.