A young monster girl named Yadamon is banished from her home in Witch Forest by her mother, the queen, as punishment for causing too much magical chaos. The queen also has a secret motive for sending her daughter away: a hidden passion for human books and magazines, which she can now indulge while keeping a magical eye on Yadamon from afar.

Yadamon arrives in a human world far different from the one the queen remembers. It has become extremely high-tech, and many natural animal species have gone extinct. She finds herself on Creature Island, a research facility where extinct animals are being genetically recreated. There, she meets a human boy named Jean and his parents, Edward and Maria, who become her first friends in this strange new environment.

Driven by intense curiosity, Yadamon constantly stumbles into misadventures that cause trouble for the humans around her. Her guardian fairy, Timon, is frequently tasked with cleaning up these messes and possesses the ability to stop time to prevent disasters. As Yadamon struggles to adapt to human society and learn control over her own powers, a far greater danger emerges. Kira, an evil witch who was sealed inside a volcano by the queen and the great witch Beril, has broken free. Seeking revenge against both the witch queen and humanity, Kira sets her sights on Creature Island and Yadamon.

The story follows Yadamon as she navigates the challenges of the human world, learns to use her abilities responsibly, and confronts the escalating threat posed by Kira. The narrative later explores the mysterious origin of strange eggs that produce an evil clone of Yadamon, threatening to bring about an apocalypse.