Ayame's Birthday and the Vanished Promise

December had just arrived in Tsukimizaka, scattering the golden leaves of the ginkgo trees along the streets and ushering in the crisp bite of winter.

In the classroom after school, Ayame Kujo smoothed the neat violet ribbon in her hair and flipped open her violet leather Unforgettable Notebook.

"Miss Hoshikawa, please compose yourself. Cease shaking the desk."

"How can I possibly stay calm?!"

Koharu leaned forward, pointing at the black card resting beside Ayame's notebook.

It was the pitch-black calling card discovered in Ayame's mailbox the night before.

"Tonight, I shall take Dr. Reiko Kujo's most precious memory. — Phantom Thief Midnight"

"Phantom Thief Midnight is targeting your mother, Ayame! And tomorrow is your eleventh birthday!"

"...My birthday is entirely irrelevant," Ayame replied with practiced indifference, pushing up her glasses. "My mother is the chief of surgery at Tsukimizaka General Hospital. She is an exceptionally busy physician who saves dozens of patients every single day. I had zero expectations for my birthday to begin with."

Koharu watched Ayame's profile as she rattled off her defense in a rapid-fire clip.

Though she acted tough, Koharu didn't miss the subtle trembling in Ayame's fingertips.

The truth was, Koharu knew. Every year on her birthday, Ayame looked forward to her mother wrapping up her hospital duties early so the two of them could climb Stargazing Hill—the highest peak in town—to watch shooting stars together. Koharu still vividly remembered the radiant smile on Ayame's face when she had shared that story last winter.

"Sorry to keep you waiting, squad!"

Taiga Inukai kicked open the classroom door, arms overflowing with an absurd mountain of crime-prevention gear.

"I've devised the ultimate strategy to capture the phantom thief! I call it 'Taiga's Patented Water-Bucket Snare Trap'! We drop a metal washbasin from the ceiling, scatter sticky birdlime across the floor, and finish him off with a deafening blast from my megaphone!"

"Rejected, Inukai."

Ayame dismissed the plan in less than a second.

"Are you intending to convert my home into a house of horrors? Phantom Thief Midnight leaps through the air without making a sound. He would hardly succumb to a slapstick cartoon gag."

"What the heck?! I spent all night coming up with that!"

"Pooock~ Ayame's cookies look so delicious-pock~"

Peeking out from Koharu's yellow cape, the little red yarn spirit Pocke tapped its mitten feet in excitement, gazing longingly at the tin of luxury butter cookies Ayame had brought from home.

"Ah... Pocke, dear..."

Ayame's cool, sharp eyes melted into shimmering hearts in an instant.

"...You gluttonous little creature. Very well, you may have a crumb. Just for you, Pocke."

"Hooray! I love Ayame-pock!"

When Pocke held the cookie crumb in both paws and nibbled away happily, Ayame clutched her chest, trembling as if overwhelmed by sheer cuteness. But catching herself, she cleared her throat with an austere cough and resumed her serious expression.

"At any rate, we must coordinate our strategy. My mother's commute follows a single road downhill from the hospital to our residence. She typically departs around five o'clock, once evening rounds conclude."

"All right, the Detectives will escort Dr. Reiko!" Koharu declared, pumping her fist.

Ayame gave a firm nod.

---

The sky above Tsukimizaka was steadily bruised by the cold shades of dusk.

Crouched behind a manicured hedge near the bend in the hospital hill road, the detectives kept watch.

Presently, a tall woman in a black overcoat draped over her white doctor's coat came walking down the slope. It was Dr. Reiko Kujo. Carrying a black leather medical satchel, she walked briskly, looking visibly exhausted from her long shift.

"It's Mother...!"

The moment Ayame whispered those words—

Dong, ding — chiming softly...

The music-box chime of five o'clock resonated through the hillside streets.

With the onset of twilight time, an icy black mist coiled upward from the base of the streetlamps.

And descending silently from the top of an ornate iron lamppost against the fiery sunset sky was a dark silhouette.

A black silk top hat, a bone-white mask, and a midnight cape drifting like living fog.

"Phantom Thief Midnight...!" Koharu cried out.

The phantom thief touched down without a whisper of sound before Dr. Reiko, placing a hand to his chest in a theatrical bow.

"Good evening, Dr. Reiko Kujo. Tonight, I have arrived to claim your most precious memory."

"Wh-Who are you...?"

The second Reiko frowned in suspicion, the thief raised a white-gloved hand.

"Leave that lost thing to me — I'll bring it home!"

Koharu leaped from the bushes.

"Pocke, let's go!"

"Leave it to me-pock!"

"Star Glass, open!"

Pocke transformed into radiant light, snapping over Koharu's left hand as the red mitten. In an instant, she wore her sunset-orange detective cape, star beret, and gripped the brass Star Glass.

"Phantom Thief Midnight, you can't take her memories!"

"My, my, if it isn't the detectives. Alas, you are too late."

The thief snapped his fingers. From Dr. Reiko's chest, a sphere of soft, shimmering cherry-blossom light was gently drawn into the air.

"Ah...!"

Within the thief's fingertips, the warm pink light darkened and hardened into a jet-black glass marble—a forget-marble.

"Mother!"

Ayame rushed forward.

Reiko staggered, blinking as if suddenly awakening from a deep daydream. But looking into her eyes, the warm, motherly affection that once shone there for her daughter was entirely gone.

"Oh... Ayame? Why are you standing out here?"

"Mother, are you all right?! What did the thief do to you...?!"

"A thief? Whatever are you talking about? I must organize the charts for my urgent surgery patients. I need to return to the hospital immediately."

"Wh-What...? B-But tonight... Tomorrow is my birthday, and tonight we promised to visit Stargazing Hill...!"

"A promise...?"

Reiko tilted her head, her voice chillingly clinical and detached.

"I have no recollection of such an agreement. I have patients whose lives depend on my surgeries. Cease these childish games at once."

Turning on her heel, Reiko strode briskly back up the hill toward the hospital.

"M-Mother...?"

Ayame stood rooted to the pavement.

Perched atop the lamppost, the phantom thief slipped the black marble into his coat, gazing down with a cool detachment.

"If you wish to reclaim the memory, discover the keepsake that binds it. ...Kujo, do not cry."

That final sentence was not delivered in his usual theatrical tone. It was a low, quiet murmur, sounding almost protective.

Swirling his midnight cape, the phantom thief dissolved into the evening fog.

"Hold it right there!" Taiga roared, but the thief had already vanished without a trace.

"Ayame..."

Koharu approached gently, but Ayame jerked her chin up.

"...It is fine. Mother is a physician. Her duty to her patients naturally takes precedence. I held no expectations from the start."

Delivering the words with icy finality, Ayame turned and began walking home alone.

Yet her retreating back looked terribly small, trembling against the cold.

---

The Kujo residence was swallowed in absolute silence.

No lights were turned on in the vast living room. Up in her bedroom, Ayame sat curled beneath a thick blanket, hugging her knees to her chest.

An enormous, empty home. Only the steady tick, tock of the wall clock marked the passage of time.

"Ugh... sniff... waaaah..."

Muffled sobs broke through the darkness of the room.

"Mother... Why... Why did you forget about me...?"

Tap, tap.

A gentle knock sounded against the balcony window.

"Eek?!"

Frantically wiping her tears, Ayame pulled back the velvet curtains. Standing on the second-floor balcony in her yellow rain cape was Koharu, holding a steaming brown paper bag.

"Ayame, can I come in?"

"M-Miss Hoshikawa?! What are you doing here... and how did you reach the second-floor balcony?!"

"I climbed up the drainpipe! Look, fresh melon bread from our bakery, and a star-shaped apple pie! Eating something sweet always brings your energy back!"

Koharu slipped through the window, setting the treats on the study table. Pocke popped out of her cape, sniffing eagerly: "That apple pie smells heavenly-pock~!"

"...Miss Hoshikawa, if you came here to offer pity, please leave. I am perfectly fine."

"No, I didn't come to pity you."

Koharu looked straight into Ayame's eyes.

"When you told me about Stargazing Hill, I was so happy. Because I love how much you love your mom! I could never turn my back on a crying friend!"

"A... friend..."

Ayame's violet eyes wavered.

"Let's win back your mother's memories! The thief said, 'Discover the keepsake that binds it.' What was the keepsake of your promise with your mom?"

Ayame bit her lower lip, then opened her Unforgettable Notebook.

"...Whenever we visited Stargazing Hill, Mother always brought along an antique brass planisphere. It is a constellation chart she gave me as a treasure when I turned five."

"That's it! Where is this planisphere right now?"

"That is the problem... I searched my room and the entire house, but it is nowhere to be found. Mother must have tucked it away somewhere..."

"All right, time for the Star Glass!"

Koharu raised the Star Glass and peered through the lens.

Pocke glowed softly on her left hand. Instantly, a slender thread of crimson light appeared through the glass.

The thread didn't stay inside the mansion; it drifted out the window, down the twilight slope, and stretched toward the imposing building perched high upon the distant hill.

"The thread is leading to the hospital...!"

"The hospital...? It can't be!" Ayame gasped. "Did Mother take the planisphere to the hospital with her...? Why...?"

"Let's go find out, Ayame! That's where your mother's true feelings are waiting!"

---

Tsukimizaka General Hospital in the dead of night.

Slipping through the staff entrance, the two girls navigated their way to the surgical department's office.

Atop Dr. Reiko's desk sat towering stacks of medical journals and patient files. Opening the top drawer, they pulled out a heavy, circular brass disc from the very back.

It was a gorgeous antique planisphere, intricately engraved with the positions of the constellations.

And tucked right beneath it was a small appointment planner.

December 1st: Ayame's birthday. View Cassiopeia from Stargazing Hill. Must wrap up all surgeries early, without fail.

Written in Reiko's precise handwriting, the note was underlined multiple times in bold red ink.

"Mother..."

Tears spilled freely from Ayame's eyes.

"Between her surgeries... she was looking at this chart, preparing for tonight. She was looking forward to my birthday more than anyone else in the world...!"

Just then—

Slam!

The heavy fire door leading to the roof rattled in the wind, letting in an icy draft.

"...Someone is on the roof-pock!" Pocke shouted.

Dashing up the metal stairs, they burst onto the moonlit rooftop. Standing there with his midnight cape billowing against the starry sky was Phantom Thief Midnight.

In his hand gleamed Reiko's black forget-marble.

"So you have tracked me even here, Detectives."

"Phantom Thief Midnight!" Koharu raised her Star Glass. "Her mother never forgot! She treasured her promise with Ayame more than anything! Return her memories right now!"

"...And what if I do?"

The thief's voice trembled with a raw, hidden ache.

"The agony of being forgotten by one's own parent... The crushing despair of losing all your memories... What could any of you possibly understand?!"

The thief spread his cape, preparing to ride the rising wind into the night sky.

"You won't escape!" Ayame shouted, raising her notebook. "Inukai, NOW!"

"YAAARRGH! DON'T FORGET ABOUT MEEE!"

Bursting from behind an air conditioning unit, Taiga unleashed a thunderous soccer kick, launching his ball straight at the thief's escape path!

THUMP!

The ball slammed violently into the rooftop railing right at the thief's feet, shattering his takeoff footing!

"What...?!"

"Pocke, high jump!"

Flaring her orange cape, Koharu launched herself off the ledge in a desperate dive.

Her target: the black marble clutched in the thief's right hand!

"GIVE IT BACK—!"

In midair, Koharu's outstretched hand lunged for his chest.

Her fingers missed the marble, but by pure chance, they caught the edge of the thief's white mask!

Snap!

The strap broke, and the white mask was torn away, tumbling into the night wind.

"Ah...!"

Revealed under the crisp moonlight was his true face.

Silky silver hair whipping in the breeze.

Wide, breathless slate-blue eyes...

"Wait...?"

Time seemed to freeze for Koharu.

(Kanata...?!)

Phantom Thief Midnight was none other than Kanata, the boy who had searched for the red rain boot with them earlier that day.

"Curse it...!"

Kanata frantically shielded his face with both hands. In the panic, the black marble slipped from his fingers, clattering across the concrete.

Ayame darted forward, scooping up the marble in a flash.

"The thief... How could it be you...?!" Koharu's voice shook.

Kanata's expression twisted in agony, and he pulled his navy muffler high over his mouth.

"...Don't look at me."

His voice was icy, yet sounded as though it were on the verge of breaking into tears.

Vaulting over the rooftop fence, Kanata threw himself into the abyss of the night.

His dark cape unraveled like black mist, and within seconds, he was completely gone.

"Ayame! Ayame, are you up here?!"

The rooftop door flew open, and Dr. Reiko stumbled out, panting for breath.

"Mother!"

Ayame rushed into her arms, pressing the brass planisphere firmly against her mother's chest.

Koharu lifted the Star Glass, her voice ringing with tender joy:

"Found you. — Welcome home, lost thing!"

As Koharu brought the forget-marble close, the dark glass fractured with a chime like crystal, melting into a warm fountain of cherry-blossom light that poured into Dr. Reiko's heart.

"Ah..."

Reiko clutched the planisphere to her chest, her eyes widening in realization.

The warm, radiant light returned to her gaze.

"Ayame...! I am so sorry... What was I thinking?! Today was your birthday... and we had made a promise...!"

Dropping to her knees, Reiko pulled Ayame into a fierce, tearful embrace.

"Mother...! No, as long as you remember me, that is all that matters...!"

Ayame buried her face in her mother's shoulder, weeping without restraint.

Looking up, a brilliant shooting star streaked silently across the crisp winter sky.

Even without climbing Stargazing Hill, the rooftop of the hospital offered a breathtaking view of the sparkling cosmos.

"It's beautiful..."

Wiping away her tears, Ayame turned around.

Standing there with a gentle smile was Koharu, watching the two of them with quiet happiness.

Ayame placed a hand over her heart and looked directly into Koharu's amber eyes.

"...Thank you, Koharu."

It was not "Miss Hoshikawa." For the very first time, she had spoken the name of her dearest friend.

"Ayame...!"

Koharu's face lit up in a radiant, beaming smile.

On the walk home.

Taiga strutted ahead, bragging loudly, "Case closed, thanks to my miracle strike!"

Koharu stopped beneath a streetlamp and slowly opened her right palm.

Caught between her fingertips when the mask had torn away was a single strand of hair.

Shining faintly in the moonlight, it was a silky silver thread.

"...Kanata."

A cold winter wind whistled down the slope, sending a shiver through Koharu's heart.

A boy with hands as cold as ice, and eyes that held such profound loneliness.

Why would he ever become Phantom Thief Midnight, stealing the precious memories of others?

"Could it really... be you, Kanata...?"

Koharu's whisper was swallowed up by the vast, silent winter sky.