Since ancient times, Japan has upheld the tradition of the 12 Zodiac signs. Eto-musumes (Zodiac girls), who have the appearance and behavior of the animals of the Zodiac, are pure hearted messengers who act as a bridge between humans and the gods. Every 60 years, the “ETM 12” tournament takes place in Tokyo’s Akihabara district, where aspiring girls from all over Japan gather for the chance to become the next zodiac sign.

The four members of Milky Holmes are going on a study tour. While soaking in the hot springs among snow monkeys, alarms interrupt the relaxing environment! It was the work of the Thief Empire. A fierce battle between Milky Holmes and the Thief Empire begins, with both sides using their Toys (special powers). Furthermore, with the arrival of the Genius 4, a three-way fight occurs! In the midst of battle, a violent lightning strikes from the sky. Struck by the lightning, the four Milky Holmes girls lose their abilities.

The story involves a boy and his younger sister whose dog Papadoll is missing. They find out that he has been abducted by anthropomorphic cats to be brought to a world called Banapal Witt, which is built on top of a giant sleeping cat. There the sun turns poor Papadoll into a bizarre giant monster. He becomes the weapon and beloved pet of a spoiled Princess who turns everything she touches into balloons. She plans to use Papadoll and a giant inflatable mouse to control the sleeping cat and thus Banapal Witt itself.