Lonely Castle in the Mirror

Lonely Castle in the Mirror (かがみの孤城) is a Japanese novel written by Mizuki Tsujimura and published by Poplar Publishing in May 2017. A manga adaptation illustrated by Tomo Taketomi was serialized in Shueisha's manga magazine Ultra Jump from June 2019 to February 2022, with its chapters collected into five  volumes. An anime film adaptation by A-1 Pictures premiered on December 23, 2022 in Japan.

Plot
Kokoro Anzai, a first-year at Yukishina Junior High School, is avoiding going to school due to bullying. She becomes uncomfortable while attending a child development support class, and has not returned to school since. One day, she finds the magical portal within the mirror at her room. While inspecting, she is dragged into the mirror and finds herself in front of a castle on an island surrounded by water. There, she is welcomed by a girl with a wolf mask. The self-proclaimed Wolf Queen introduces her to six others: Subaru Nagahisa, Akiko Inoue, Rion Mizumori, Earth Masamune, Fūka Hasegawa and Haruka Ureshino. Addressing them as Little Red Riding Hoods, the Wolf Queen instructs them to find a key hidden in the castle, which will lead them to a room where one can make a wish, before the deadline of March 30 of the following year. If anyone makes a correct wish, it will be granted and all children will lose their memories of the castle. She also tells the children to leave before 5pm. Any child who stays at the castle on the evening will be eaten by a wolf.

The seven children start spending time together at the castle, occasionally looking for the key. A year has passed, but they have not succeeded. Kokoro learns from the children that they attend the same school, except for Rion and have been avoiding school for various reasons. Planning to meet up at school, they find out that they do not exist in each other's worlds. Therefore, Masumane theorizes that they are from parallel universes, but the Wolf Queen discovers and denies this.

The deadline is nearing, but they have not found the key yet. In the meantime, Kokoro has opened up to her mother about being bullied and with the help of her teachers tries to resolve the issue. The others have also taken steps forward.

On the second to last day, Kokoro finds an illustration titled "The Wolf and the Seven Young Goats", and realizes that this was a clue to the key's location. As she returns home, she discovers the mirror shattered into pieces. She learns from the children that Aki broke the rule and stayed at the castle after 5pm. The rest of them are eaten by the wolf, due to their responsibility. Kokoro passes through the broken remnants of the mirror, and uses the clues in the illustration to find the key. She sees fragments of the memories of her friends and learn they all had suffered from various problems such as bullying. Suffering bullying and harassment, Aki took refuge at the castle. Kokoro uses her wish to save her friends. Upon being resurrected, Aki reconciles with them.

Before they have to return and forget about the castle, they realize that they were in fact from the same universe but from different timelines spanning over 40 years. They carve their names on the wall and bid one another farewell. After all of them have passed through, Rion confronts the Wolf Queen, and it is revealed that she is his late sister, Mio. She removes the mask and bids him farewell. Back in her own timeline, Kokoro reunites with Rion and they head to school together.

Characters

 * Kokoro (こころ)
 * A junior high school girl and the last person to enter the castle through the mirror's magical portal, when she comes from the middle of 2000s.
 * A junior high school girl and the last person to enter the castle through the mirror's magical portal, when she comes from the middle of 2000s.


 * Aki (アキ)
 * The second person who came from the early 1990s. After avoiding her abusive stepfather and losing her boyfriend, the timeline reveals in the past that Aki changed her surname and became a school counsellor.
 * The second person who came from the early 1990s. After avoiding her abusive stepfather and losing her boyfriend, the timeline reveals in the past that Aki changed her surname and became a school counsellor.


 * Rion (リオン)
 * A junior high school boy and a soccer player at a boarding school Hawaii. His sister died when he was a child. Rion is the third person who came from the same decade like Kokoro.
 * A junior high school boy and a soccer player at a boarding school Hawaii. His sister died when he was a child. Rion is the third person who came from the same decade like Kokoro.


 * Subaru (スバル)
 * The first person who came from the middle of 1980s. His goal is to become a video game designer.
 * The first person who came from the middle of 1980s. His goal is to become a video game designer.


 * Fūka (フウカ)
 * A pianist and the sixth person who came from the early 2020s.
 * A pianist and the sixth person who came from the early 2020s.


 * Masamune (マサムネ)
 * The fifth person who came from the early 2010s. His first name is "Earth".
 * The fifth person who came from the early 2010s. His first name is "Earth".


 * Ureshino (ウレシノ)
 * The seventh and final person who came from the middle of 2020s.
 * The seventh and final person who came from the middle of 2020s.


 * Wolf Queen (オオカミさま)
 * A girl with the wolf mask. She reveals to be Rion's late sister Mio.
 * A girl with the wolf mask. She reveals to be Rion's late sister Mio.


 * Kitajima-sensei (喜多嶋先生)
 * The future version of Aki and Kokoro's school counselor.
 * The future version of Aki and Kokoro's school counselor.


 * Kokoro's mother (こころの母)
 * An unnamed woman. She helps her daughter overcome her negative emotions.
 * An unnamed woman. She helps her daughter overcome her negative emotions.

Novel
Written by Mizuki Tsujimura, Lonely Castle in the Mirror was originally published by Poplar Publishing on May 11, 2017. The company re-released the novel in a two-volume paperback format in March 2021. The novel was published in English by Doubleday in April 2021.

Manga
A manga adaptation illustrated by Tomo Taketomi was serialized in Shueisha's manga magazine Ultra Jump from June 19, 2019, to February 19, 2022. Shueisha collected its chapters into five volumes, published from December 2019 to May 2022.

The manga is licensed in North America by Seven Seas Entertainment.

Anime film
An anime film adaptation was announced on February 24, 2022. It is produced by A-1 Pictures and directed by Keiichi Hara, with the script written by Miho Maruo; character designs handled by Keigo Sasaki, who also serves as chief animation director; visual concept and castle design by Ilya Kuvshinov; and music composed by Harumi Fuuki. Yuuri performed the film's theme song "Merry-Go-Round" (メリーゴーランド). The film premiered in Japan on December 23, 2022. GKIDS acquired the rights to the film in North America, and screened it in Japanese and English-language formats on June 21–22, 2023. The film premiered on television for the first time on Nippon TV's Kin'yō Road Show programming block on February 9, 2024.

Reception
The novel placed first in Kadokawa's Da Vinci magazine "Book of the Year" list in 2017. It also won the Japan Booksellers' Award in 2018.

The anime film adaptation debuted at 6th at the Japanese box office, earning ¥140million (US$1.05million) on its opening weekend. It was well-received by audience, and was rated 3.94 out of 5 on its first day on Filmarks. Richard Eisenbeis of Anime News Network gave the film a 'B-', applauding its social commentary on bullying in Japan and its relatable cast of characters, but criticizing its plot twists, which are 'easy to see coming'. Writing for The Japan Times, Matt Schley gave the film 3 out of 5 stars, praising its social commentary and its characters as well while criticizing the direction of the film, which 'lacks anything resembling subtlety', noting its 'overbearing' soundtrack 'commanding its audience to feel at any given moment'. In 2023, the film was nominated for Animation of the Year at the 46th Japan Academy Film Prize.