Seventh-grader Umbra was born with a rather unique, yet incredibly destructive power. But because of her traumatic childhood experiences, she rarely uses it and has grown to hate her own powers. Unfortunately, Umbra gets placed in a situation where she is forced to use her powers now more than ever, as she wakes up in a place far from her hometown, not knowing how she got there and having to deal with the sudden rise of an unknown Demon Lord.