A 43-year-old company employee named Tomakomai suffers relentless power harassment from his boss, culminating in a bizarre form of magical harassment where he is forced to transform into a magical girl. After this involuntary transformation, he causes massive destruction in his surroundings and finds himself unable to return to his original form. Now inhabiting the body of a classic magical girl, Tomakomai seeks refuge in a peculiar squatter settlement known as the Magical Girl Village, a place illegally occupied by others who share his impossible condition. The series follows his new life among these immortal and chaotic beings.

The setting is the Magical Girl Village, an area of a city that has been taken over by a group of immortal magical girls who are considered dangerous anomalies by human society. The village is a place of contradictions, depicted as both a realm of madcap, absurdist humor and one of underlying madness and despair. Life there is eternal, and its residents, having lost the ability to die, pass their days in idleness, binge eating, and drinking, with the ruins of their humanity occasionally surfacing.

The protagonist, Tomakomai, is a middle-aged salaryman now stuck in a stereotypically cute magical girl form. His primary hobbies are eating and causing unintentional mayhem. He is surrounded by a cast of eccentric, immortal magical girls. Nemuro is a perpetually cheerful but heavy-drinking magical girl whose true thoughts are hard to read. Haruho is the village chief, an alcoholic who has lost count of her age. Kushiro is Haruho's self-proclaimed greatest attendant. Kanagawa is a long-suffering government employee from the Anti-Magical Girl Agency who desperately tries to mediate between humanity and the village. Other residents include Shiraoi, a dim-witted magical girl wrapped in bandages who often serves as comedic relief, and a silent, menacing schoolgirl named Sarufutsu who secretly holds a noble desire to preserve humanity.

The narrative unfolds in short, absurdist vignettes. One notable early arc involves Tomakomai being introduced to the village and its nonsensical rules, such as a tour guided by a love-obsessed macho man. Another recurring thread follows the daily struggles of Kanagawa as he attempts to manage the village's illegal occupation and the magical girls' unpredictable, often dangerous, behavior. The series contrasts its primary gag-driven comedy with moments of stark darkness, exploring the horror of eternal existence. The magical girls are treated as immortal disasters, and story arcs occasionally shift to reveal their deep-seated despair and loneliness, presenting their chaotic village life as a form of endless, hopeless limbo. However, Tomakomai's lingering humanity and pragmatic, unglamorous perspective gradually begin to influence the other residents, offering a strange form of solace and change within their otherwise stagnant, insane world.