空っぽの少女と虹のかけら (Series) favorite_border

[DeepL Translation - needs review] Volume 1 Introduction: Ayuko, a girl who is no longer needed by anyone in the world and has lost her emotions. One day, on a field trip, a mysterious voice lured her to another world inhabited by non-humans. As she wanders around, a boy wearing a strange mask appears in front of her. ...... A dark fairy tale about a "piece of rainbow" begins.

(Translator: DeepL)