Mysterious Disappearances

Sumireko Ogawa is a bookstore clerk who dreamed of writing novels in her youth. She teams up with her coworker, Ren Adashino, who is hiding secrets of his own, to investigate supernatural phenomena happening in the city. ==Characters==

; : :A 28-year-old woman, first discovered her passion for writing as a teenager but struggled to maintain her creative drive as she grew older. While working at a bookstore, she stumbled upon a mysterious grimoire—one that accidentally transformed her back into a child. Without Ren's timely intervention, the magic would have killed her. Now, she assists Ren and Oto in solving supernatural mysteries across Tokyo. Having absorbed some of the grimoire's power, Sumireko can freely shift between her adult and child forms. ; : ; : ==Media==

Manga Written by and illustrated by , Mysterious Disappearances started on Shogakukan's '''' website on October 18, 2019. Shogakukan has collected its chapters into individual volumes. The first volume was released on April 10, 2020. As of December 12, 2025, ten volumes have been released. Volumes Anime An anime television series adaptation was announced on January 12, 2023. It is produced by Zero-G, and written and directed by Tomomi Mochizuki, with character designs handled by Takuya Tani, and music composed by Kayo Konishi and Yukio Kondō. The series aired from April 10 to June 26, 2024, on AT-X and other networks. The opening theme song is "Hazard Symbol", performed by Yuyu, and the ending theme song is , performed by Nonoka Ōbuchi. Crunchyroll streamed the series worldwide excluding Japan and China. Episodes ==Reception==

In 2020, the manga was one of the nominees for the sixth Next Manga Awards in the web category. The manga was recommended in 2021 by manga artist Akihito Tsukushi. ==Notes==