Hiiragi Kyoichiro, the wealthy family's eldest, departs his village for Imperial University in Tokyo, toting a treasured katana and a peculiar ability to see spirits. His optimistic outlook shifts when he wakes up smaller and undeniably adorable, a consequence of his wish. Amidst a brewing supernatural clash involving rival Imperial Army factions, an enigmatic figure, and the rebellious Five Katana group, Kyoichiro's world plunges into turmoil.