Lonely Castle in the Mirror - Recommendations

Alt title: Kagami no Kojou

If you're looking for anime similar to Lonely Castle in the Mirror, you might like these titles.

Harukanaru Toki no Naka de ~Ajisai Yumegatari~

Harukanaru Toki no Naka de ~Ajisai Yumegatari~

Azusa was a normal high school student, until she was sucked down a well into a fantasy world full of monsters, demons, and surprises. Dubbed the priestess of the land of Kyou, she found herself joined by the Hachiyou, a group of people with magical powers, dedicated to protecting the priestess and the land. But all does not bode well for Azusa, as the demon Akuram wishes to claim her power for evil purposes. In addition, a malicious spirit is ravaging the townspeople, stealing their life energy! A day's work is never done for the priestess and her companions, it seems.

El-Hazard: The Alternative World

El-Hazard: The Alternative World

Taking place after the second Magnificent World OVA, Mr. Fujisawa has finally married Miz, who has retired her position as Priestess of Water. In her stead, a young woman named Qawuul is brought in as the priestess, and in the tradition of the El Hazard series, falls for Makoto. However, the calm is yet again broken as the gang is transported into yet another alternate world by a mysterious man named Arjah, where new trials and mishaps as well as a new adventure awaits.

Hitoshizuku-P × Yama△: Kaizoku F no Shouzou

Hitoshizuku-P × Yama△: Kaizoku F no Shouzou

Suisei no Fräulein: Prologue

Suisei no Fräulein: Prologue

Morita is a boy who is transported to another world and takes on the task of saving it by becoming an idol producer to fairies and demi-humans.

Arata the Legend Picture Drama

Arata the Legend Picture Drama

No Longer Human: In Another World

No Longer Human: In Another World

An adventure in another world with cute girls by your side and video game-like powers–sounds like an anime fan’s dream, right? Not so for melancholic author Osamu Dazai, who would quite literally prefer to drop dead. Video games haven’t even been invented yet when he gets yanked into another world in 1948. Really, all the fantastical adventure he keeps running into is just getting in the way of his poetic dream of finding the perfect place to die. But no matter how much he risks his hide, everything seems to keep turning out okay. 

Saikyou Onmyouji no Isekai Tenseiki

Saikyou Onmyouji no Isekai Tenseiki

Haruyoshi is the strongest onmyouji in his world. He's betrayed by his friends and, on the verge of death, he wishes to be happy in his next life. He then attempts a secret reincarnation spell. The spell is a success and he is reincarnated, but somehow it's in another world. He is reborn into a distinguished family of wizards, but is judged to have no magical ability. He soon realizes however that the magic in this world is nothing compared to his old onmyou arts, and he declares that he doesn't need magic. He thus begins his easy life in another world with his onmyou arts and a multitude of youkai creatures who follow him.

Cinnamon the Movie

Cinnamon the Movie

El-Hazard: The Wanderers

El-Hazard: The Wanderers

Jinnai has sabotaged Makoto's science project, and while he is working on it, it malfunctions and sends the two of them as well as Jinnai's sister and Mr. Fujisawa, a history teacher, into an alternate dimension. After arriving in this new world, each character finds his/her own adventure is about to begin, from taking over an empire of evil bugs to rescuing a princess of Rushtaria.

Seven Days War

Seven Days War

On the day before summer vacation, every boy in a first-year class of a downtown Tokyo middle school disappears. Was it some accident? A mass kidnapping? Actually, the boys holed themselves up in an abandoned factory on the riverbed. With support from the schoolgirls, the boys start a revolution against the adults from this "liberation zone."