Warning: The following contains spoilers for Mysterious Disappearances episode #3!!
Almost every aspect of Mysterious Disappearances on Crunchyroll is unconventional, especially the small part of its story that makes this new series a reverse isekai, even though it’s not official. However, these idiosyncrasies work quite well, especially since nothing about the series suggests that it will do anything except maybe cover instances where some things disappear, all of which possess an air of mystery. So the audience doesn’t really have any expectations. Ironically, even though the name of the anime itself is actually quite unconventional for being so direct, it, like the fad of longer titles, is actually quite misleading.
Mysterious Disappearances can be considered a reverse isekai, since the actions of the equally mysterious Ren Adashino are to help a little girl named Oto return to her home world. However, this isn’t discovered until the second episode, which is what makes this obvious indirect association to reverse isekai so unexpected.
The sub-genre, like isekai itself, is quite massive, and most series try to capitalize on any connection, regardless of how small. Rather appropriately, there are quite a few additional instances where Mysterious Disappearances strays from the beaten path, including how the series approaches seinen and explores the source of these eponymous departures.
Mysterious Disappearances also immediately breaks the format that the debut episode implied the series would keep. It becomes clear by the end of episode #1 that Ren Adashino will be collecting themed supernatural books that affect their owners a certain way. Fans understandably concluded that Mysterious Disappearanceswould follow a conventional episodic format, where either every episode or collection of them for more complex stories would explore each of these books and then move on. Of course, later episodes introduce even more relics that are known collectively as Curiosities.
As a result, it was assumed that the story of the first woman who came across such a book named Sumireko Ogawa would end once her tome, which can bring back the owner’s youth, was collected. Most anime that follow an episodic format treat each of its individual stories as complete isolated incidents, especially their main characters, like in The Witch and the Beast. Only sometimes do these characters return. However, episode #2 not only begins with Sumireko, but her new youth-activating powers associated with her special book play a major role in Ren’s overall quest to collect them all.
It’s the thematic nature of how Sumireko’s supernatural abilities connect with her identity as an aspiring novelist that positions Mysterious Disappearances in another unconventional light. Sumireko was only a good novelist when she was younger, and now she can physically revert to earlier times in her life. This type of storytelling is mostly aligned with shonen, and yet, Mysterious Disappearances is a seinen. Similarly to how the book’s supernatural powers complement and complicate Sumireko’s aspirations and dreams, she also redefines the purpose of these abilities to help her in a completely different albeit plausibly connected way, which shonen also does quite well. She capitalizes on the smaller and larger forms to help her on a physical level beyond helping her write novels.
In what further underscores the unconventional nature of its overall format, this whole dynamic is appropriately expanded upon during its second story, which would have normally excluded her if Mysterious Disappearances were like most episodic series. Not only does Sumireko’s ability to become younger play an important role in the next adventure, but her real age soon creates a compounding effect when she presents herself as a younger person, augmenting normal teenage lies to a more intense degree since she’s much older.
Mysterious Disappearances is so unconventional, not just because it incorporates elements of reverse isekai unlike how most series officially in the genre attempt to do so, but due to the fact that the new Crunchyroll series defies the usual structure of most episodic series while acting like a shonen even though it’s officially a seinen.