Jahy is the feared second-in-command of the Dark Realm until a magical girl shatters the mana crystal that powers it, collapsing her world and leaving her stranded in the human one. Shrunk to the body of a child and stripped of nearly all her power, the once-mighty demon ends up in a cramped one-room apartment, scraping together rent and clocking in at a part-time job while plotting to rebuild the realm she lost.