The Modern Shelf

The timeline

• 1930s–40 — Aka-manto (the shelf's pre-war floor): the red cloak spreading down the Tōkaidō by mouth alone; the censorship-origin theory (the 1936 coup's unspeakable news as a child-taker); the no-win question format the kuchisake-onna would perfect.
• 1978–79 — Kuchisake-onna: the last street panic — police deployments, school group-walks, a documented curve that "subsided during summer vacation": the monster kept school hours.
• 1950s→1990s — Hanako-san: the school toilet's tenant, carrying (per the JA record) the red garment of the abolished privy-god cult — the schoolyard unknowingly maintaining a Shinto station.
• 1980s — Kyonshii: the import control-specimen — one marketing cycle, zero localization, eternal receptor-sites.
• 1978→2025 — Issie: the lake-deity-to-cryptid pipeline with a complete economic lifecycle, gift shop to closure.
• 2001 — Kunekune: 2ch's field-glare minimalism; don't-look reduced to its atom.
• 2002 — Ningen: the sea-giant redrawn white; the legend growing where an industry had genuine secrets.
• 2005 — Kotoribako: the loaded box; the shelf's cautionary case (see register rules).
• 2008 — Hasshaku-sama: systems-netlore — dōsojin seals, broken bindings, the kin-convoy escape: "traditional hardware in a new chassis."
• 1990s Shibuya — the shichinin-misaki variant: the conserved-seven mechanism transplanted intact to the city's slopes.
• Undated, and the shelf's darkest — Teke Teke: the schoolgirl severed at the waist on a northern railway line, running on her elbows. Undated on purpose: the legend has no first printing we can point to, which is itself the finding — the modern wing's best-timed members are the ones that were born online. Read her grievance closely and she is not a modern invention at all: she died "as a result of the station staff's neglect" — not the train, the institution, which is Oiwa's grammar exactly, relocated to a platform. Her sibling Kashima Reiko asks "where are my legs?" and, like every question-trap here, ships with a memorized exit (kamen shinin ma). The Satchan children's-song link is internet-era accretion and labeled as such.
• The vanishing point — Ushi no Kubi: the story that is only a reputation; "the perfect yokai is the one the tradition never has to produce."

What the shelf shows

Nothing on it is new. The tall woman, the sea-giant, the bound power, the school spirit, the toll-voice, the don't-look rule — every modern hit is the tradition's old machinery re-fired through new media (mimeograph rumor, television, film distribution, forum post), at accelerating cadence and with better timestamps than anything in the Edo record. The modern shelf is therefore the authenticity-spectrum's laboratory: the only era where we can watch accretion happen in real time, author by author, post by post — which is exactly what must have happened in every earlier century, unrecorded. The internet didn't change Japanese folklore; it put the workshop under glass.

One pairing to end on, because it measures the century better than any date on the list: the betobeto-san is a sound behind you on a mountain road, and you dismiss it by stepping aside and saying "after you." The teke teke is a sound behind you on pavement, and it is coming to cut you in half. Same motif — the follower you cannot see — a century apart. The courteous ghost of the mountain road became the mutilated one of the station platform. Urbanization, audible.