Ichigo Momomiya is excited to start high school and fall in love. She is in luck when she meets the popular and good-looking Masaya Aoyama, and she immediately develops a crush on him. When Ichigo learns that Aoyama is passionate about the environment, she seizes the chance to ask him out thanks to some tickets to an exhibition about endangered animals. During their date, Ichigo is struck by a mysterious light and faints. Waking up to the sight of Aoyama, she remains unharmed—but they both must escape from a giant rat-like creature after it injures Aoyama. To save her crush, Ichigo awakens her powers and transforms into a heroine with the skills of a cat. After she defeats the monster, researchers Ryou Shirogane and Keiichiro Akasaka explain that Ichigo was chosen to become a part of the Mew Project: a group of five magical girls whose DNA has been infused with those of certain endangered species. Now, Ichigo must find the rest of her teammates to defeat the Chimera Anima—beings infected by aliens who want to take over the world—before it is too late.

Adaptation of Takashi Noguchi's manga, which itself adapts Baku Yumemakura's supernatural romance novel. The original novel is about a 12th-century man named Minamoto no Yoshitsune (Kurou). Kurou flees into the mountains after losing to his brother Minamoto no Yoritomo, the first Shogun to rule all of Japan. History records that he committed suicide, but instead, Kurou meets a strange, beautiful woman named Kuromitsu in her mountain hermitage. Eventually, Kurou falls in love with Kuromitsu, but then realizes she conceals a dark secret. He learns that he is unable to die and continues to live for a thousand years as Japan evolves into a future society.

Black Cat Cafe is located in the fifth ward of the Imperial Capital. Having lost their purpose after the war ended a few years prior, advanced mechanical dolls known as Automata have been restored and now work at the cafe wearing elegant kimonos. While they adjust to the peaceful world, events of the past continue to haunt the Automata, preventing them from letting go of the responsibility they once held. Among the Automata working at Black Cat Cafe is the recently restored Haizakura, who has lost her memories during a reset. Her identity and role in this unfamiliar world are a mystery to her, but one thing is certain—she loves to sing. With never-ending curiosity and beautiful songs to guide them, Haizakura and the Automata search for their new purpose together, supporting each other no matter how rigorous that endeavor might be.

These are witches who defend everyone's smiles and fight enemies through the healing power of music. These witches, opposite of those in the defense fleet, are idols known as the Music Squadron.