Hiniiru

A mysterious black object fell from the sky a decade ago, annihilating a city. Kagerou and Momiji were young when it happened and have since grown up together under the enigmatic structure. Despite a strong bond between them, Kagerou hesitates to express his feelings, doubting his ability to protect her. When the structure releases strange spheres that consume and mutate people, Kagerou and Momiji are affected. Kagerou is recruited by an organization that identifies him as an "ember," while Momiji is classified as a "dross," a non-human subject for experimentation. Refusing to accept this, Kagerou resolves to use all his strength to safeguard the girl he cares for.