Episode 9: ‘The Vanishing Key’ (Unsolved Cases Arc)
A rainy May night wraps Kūrenai high school in shadows. The police sirens haven’t yet faded, but whispers spin wild chills. Students saw a crime, but now, a clue’s lost. How do you react when even teachers are out of answers? Would you keep your secrets safe?
Protagonist: Yuuta Mineshima. He wants to clear his sister’s name. Without proof, he might lose her trust, and herself. His stubborn streak keeps him chasing clues far past curfew.
Supporting: Hana (his sharp-tongued best friend), Sakaki (a rogue bike gang rookie), and Mizuno (old-school science teacher with a kind eye but a quirk for random trivia). Together, they track odd loose ends the adults won’t follow.
Late that night, the group sneaks to the forbidden old annex. Boards groan, mold flights. Hana nudges Yuuta. “Give me the flashlight. I’m not tripping in here for your pride.” She rolls her eyes when he won’t. Outside, thunder leaks gold through dusty cracks. Somewhere, metal clinks. There’s tension—you feel it in the sick clock tick.
The stolen key. Mrs. Ashizawa, the lonely librarian, lost it days before. Someone used it for a break-in, but was it her mistake alone? Yuuta finds shoe marks in the library basement: narrow and hollowed. Hana snags a torn patch of dark cloth caught on the lockers.
The next day, Sakaki bails on class. Rumors surge. They say he was part of the incident—maybe even stole the key himself. Yet, Mizuno vouches for his alibi: map storage, sorting outdated folders. Students split in two. Most believe he’s lying. Yuuta’s not so sure. You can’t fake that stunned, honor-bound look Sakaki wears in the boys’ room at noon.
After dark, Yuuta and Hana tail Sakaki to White Lily Shrine. Behind stone pillars, they overhear girls trading gossip for payment. But one girl’s cry tells the truth—it’s not gossip at all. “I saw a teacher. He came through that door. Sakaki just watches, but he’s not bad. But he knows.” Hana swears as a figure darts past to leave a thin, square card at the shrine’s base. It’s marked in red: a date—the night of the crime. Should Yuuta grab it? Would you?
They argue. Mizuno texts: ‘THIS CAN HURT YOU BOTH. Get out.’ That tight gut feeling, right? Against her own words, Hana risks it and sprints to get the card. The silhouette of a teacher shifts in the shadows. Mizuno’s voice joins. “Don’t run, Yuuta-san. Stay close to the lantern.”
The teachers meet the group at the school gate. Mr. Shiomi stares like he knows their plans. Yuuta feels dread, knowing what’s at stake. Someone planted this evidence to shift blame. Next day, rumors and sickly grins follow. Hana refuses to talk. Sakaki disappears. Does silence hide pain, or buy time?
Halfway through the episode, flashbacks sketch old dorm fires, bitter snubs, one secret angle of poor Sakaki’s shoe from a hall camera reel. Was someone setting him up for years? Students mention strange video flickers at odd times. Coincidence or cover-up?
The three collect what they find. Hana watches video again. Still nothing obvious—except the flicker. A blur at 1:43AM: not Sakaki, but tall, haunted Mr. Shiomi. Does a chill run down your spine? 
Sakaki gets a message, ‘Go River—midnight.’ The team agrees to follow, scared and drawn. Deep fog grips the Sugai bridge. There’s movement under wavering orange light. Yuuta moves closer. His hand tightens on the phone. You’d do the same, right? A voice echoes—a call for mercy, regret, maybe confession?
He turns and sees Mizuno perched calmly in the cold, with a second, old key in her hand: she’s been hiding more than facts. As voices rise, footsteps close. Is it police, or someone keen to shut the case forever? The arc cuts off, curtain falling with a stuttering phone light, nerves raw, every secret growing into another shadow.
Have you ever wanted to step inside a story and solve it yourself? The lines of justice keep blurring. Will Yuuta keep chasing, or get lost with the others? And does everyone guard a crime beneath their wordless fear?
