Shy outcast Kokoro has been avoiding school for weeks when she discovers a portal in her bedroom mirror. She reaches through and finds herself transported to an enchanting castle where she is joined by six other students. When a girl in a wolf mask explains that they have been invited to play a game, the teens must work together to uncover the mysterious connection that unites them. However, anyone who breaks the rules will be eaten by a wolf.
Unfortunately the movie Lonely Castle in the Mirror is not yet available on HBO Max.
| Writing | Mizuki Tsujimura | Novel |
| Writing | Miho Maruo | Screenplay |
| Visual Effects | Keigo Sasaki | Character Designer |
| Sound | Harumi Fuuki | Original Music Composer |
| Directing | Keiichi Hara | Director |
| Visual Effects | Keigo Sasaki | Supervising Animation Director |
| Sound | Yuuri | Theme Song Performance |
| Art | Ilya Kuvshinov | Concept Artist |
| Production | Toshihiro Takahashi | Executive Producer |
| Production | Keiichi Sawa | Executive Producer |
| Production | Atsuhiro Iwakami | Executive Producer |
| Production | Norihiro Miyamoto | Executive Producer |
| Production | Hitoshi Chiba | Executive Producer |
| Production | Mitsuhisa Ishikawa | Executive Producer |
| Production | Hiroshi Chino | Executive Producer |
| Production | Masahiro Tadano | Executive Producer |
| Production | Tomohiro Kato | Executive Producer |
| Production | Hiroyuki Nakajima | Executive Producer |
| Production | Ken Kozakura | Executive Producer |
| Production | Kenichi Hirose | Executive Producer |
| Production | Nobuyuki Iinuma | Executive Producer |
| Production | Shigeaki Yoshida | Executive Producer |
| Production | Kei Kushiyama | Producer |
| Production | Hirotaka Aragaki | Producer |
| Production | Sota Furuhashi | Associate Producer |
| Production | Shuhei Akita | Associate Producer |
| Production | Akiho Katayama | Associate Producer |
| Art | Hiromichi Ito | Art Direction |
| Art | Takashi Nakamura | Art Designer |
| Visual Effects | Takahiro Mogi | Color Designer |
| Visual Effects | Shigetaka Ushida | CGI Director |
| Visual Effects | Hiroshi Inagaki | CGI Director |
| Camera | Toshiaki Aoshima | Director of Photography |
| Camera | Yohei Miyawaki | Director of Photography |
| Editing | Shigeru Nishiyama | Editor |
| Sound | Mami Takaishi | Music Producer |
| Directing | Takayoshi Nagatomo | Second Unit Director |
| Editing | Maki Sendo | Assistant Editor |
| Visual Effects | Toshiyuki Inoue | Key Animation |
| Visual Effects | Akiko Itagaki | Animation Director |
| Visual Effects | Kouji Shiyouki | Animation Director |
| Visual Effects | Chiaki Furuzumi | Animation Director |
| Visual Effects | Tomomi Kawatsuma | Animation Director |
| Visual Effects | Toko Uchimura | Animation Director |
| Visual Effects | Tetsuya Kawakami | Animation Director |
| Visual Effects | Tomoko Katasho | Animation Director |
| Visual Effects | Keigo Sasaki | Animation Director |
| Visual Effects | Shigehito Tsuji | Key Animation |
| Visual Effects | Shinichi Mogi | Key Animation |
| Visual Effects | Kouichi Arai | Key Animation |
| Visual Effects | Hiroyuki Nishimura | Key Animation |
| Visual Effects | Toko Uchimura | Key Animation |
| Visual Effects | Shino Kuzuhara | Key Animation |
| Visual Effects | Hiroko Oguri | Key Animation |
| Visual Effects | Hiroki Takiguchi | Key Animation |
| Visual Effects | Ayaka Minoshima | Key Animation |
| Visual Effects | Norio Matsumoto | Key Animation |
| Visual Effects | Mark Corcoran | Key Animation |
| Visual Effects | Li Jianxiu | Key Animation |
| Visual Effects | Michiyo Suzuki | Key Animation |
| Visual Effects | Jun Uemura | Key Animation |
| Visual Effects | Kazuho Suzuki | Key Animation |
| Visual Effects | Kazuma Tanaka | Key Animation |
| Visual Effects | Kumiko Ozawa | Key Animation |
| Visual Effects | Moe Wada | Key Animation |
| Visual Effects | Yuuma Yokomatsu | Key Animation |
| Visual Effects | Mitsuaki Hori | Key Animation |
| Visual Effects | Kanako Ueda | Key Animation |
| Visual Effects | Keiichiro Honjo | Key Animation |
| Visual Effects | Yuika Kojima | Key Animation |
| Visual Effects | Kazuko Hayakawa | Key Animation |
| Visual Effects | Akiko Itagaki | Key Animation |
| Visual Effects | Miyuki Ishizuka | Key Animation |
| Visual Effects | Katsushi Morita | Key Animation |
| Visual Effects | Ririko Minami | Key Animation |
| Visual Effects | Maki Toyota | Key Animation |
| Visual Effects | Yuuko Sera | Key Animation |
| Visual Effects | Kyohei Yamamoto | Key Animation |
| Visual Effects | Ken Takahashi | Key Animation |
| Visual Effects | Miyuki Honda | Key Animation |
| Visual Effects | Tomonori Ota | Key Animation |
| Visual Effects | Meiko Uenoyama | Key Animation |
| Visual Effects | Mami Uebayashi | Key Animation |
| Visual Effects | Kaito Hashimoto | Key Animation |
| Visual Effects | Shingo Adachi | Opening/Ending Animation |
| Visual Effects | Masaaki Takiyama | Opening/Ending Animation |
| Visual Effects | Yumi Kuroiwa | Opening/Ending Animation |
| Visual Effects | Akiko Itagaki | Opening/Ending Animation |
| Visual Effects | Meiko Uenoyama | Opening/Ending Animation |
