Earth, where magical girls emerged with the help of the fairy realm to stop the sudden invasion of the demon world 20 years ago. And Magical Rampage, a man who has been a magical girl for 15 years, making him essentially the most senior magical girl. At some point, he became unable to return to his original form and is destined to live as a magical girl for the rest of his life. Nevertheless, with the sole determination to protect humanity, he continues to mercilessly kill all enemies. This is the story of a magical girl who keeps growing stronger with the singular goal of destroying the demon world.