Legally Submittable Anime Paperwork
Japan's "oshi-katsu" fan culture has reached government paperwork. Konin Todoke Seisakusho, the country's top seller of designer marriage registration forms, has partnered with the Oshi no Ko anime for a line of character-themed certificates that couples can actually file at their local municipal office. Japanese anime news site Anime Anime reported the collaboration launched today, June 26, 2026.
The company says fans increasingly buy themed registration forms to "share an important day with a favorite character." Many buyers reportedly display the included commemorative certificates at home alongside other collectibles even after filing the real paperwork.
What's in the Lineup
Four products make up the collection, each available in six character designs: Ai, Aqua, Ruby, Arima Kana, Kurokawa Akane, and MEMcho.
The Marriage Registration Set (¥3,300, roughly $22) comes with two A3 marriage registration forms, an A4 commemorative marriage certificate for display, and an acrylic stand. The Birth Registration Set (¥3,520, roughly $23) adds naming paper and extra display certificates to a similar package. Both use premium Japanese-made paper and meet the formatting requirements for municipal submission.
Rounding out the line are life-size posters (¥6,050, roughly $40) printed on water-resistant, wrinkle-resistant synthetic paper at 180 cm tall, and clear files (¥550, roughly $3.60) for the budget-conscious collector. Everything is available on Konin Todoke Seisakusho's online store and Amazon Japan.
The "Oshi-Kon" Trend
The collaboration taps into what the Japanese merch industry calls "oshi-kon" (a portmanteau of "oshi," meaning favorite character, and "kon" from "konin," meaning marriage). Designer marriage certificates featuring anime characters have become a growing niche as fan culture extends to life milestones. Buyers treat them as both functional documents and collector's items, displaying them alongside figures and other goods.
Konin Todoke Seisakusho already offers character-themed forms for franchises like Sailor Moon and Peanuts. Oshi no Ko, with its 25-million-copy manga and three anime seasons under its belt, fits naturally into that catalog. The manga by Aka Akasaka and Mengo Yokoyari wrapped its serialization in Shueisha's Weekly Young Jump in November 2024 at 16 volumes, and the anime's Season 4 Final Season is currently in production.
Looking Ahead
Oshi no Ko's Season 4 Final Season has been confirmed but has no broadcast date yet. The franchise also expanded into live-action territory with an Amazon Prime Video drama series and a theatrical film in 2024. For international fans, Oshi no Ko's anime seasons stream on various platforms including Amazon Prime Video. The source manga is available in English through Yen Press.
The collab merch is sold through Japanese retail channels only. International buyers will need to use a proxy shipping service or Amazon Japan's global shipping option where available.