Miyo Sasaki, nicknamed "Muge" (infinitely mysterious), is a 14-year-old girl defined by profound duality. She exhibits an outwardly energetic, rambunctious school persona, openly expressing emotions and aggressively pursuing classmate Kento Hinode romantically. This cheerful facade masks deep-seated pain from her family background: her biological mother's abandonment and a strained relationship with her stepmother, Kaoru Mizutani, whom she initially rejects, formally calling her "Ms. Kaoru." Unresolved trauma fuels Miyo's depression, feelings of worthlessness, and desire to escape reality, leading her to declare hatred for the world and wish for its end. Living with her father and stepmother in Tokoname, known for its pottery heritage, familial tensions—including unresolved conflicts between her biological mother and stepmother—deepen Miyo's isolation. She perceives most people as emotionally distant "scarecrows," a coping mechanism against further rejection or abandonment. This detachment extends to school, where past elementary bullying leaves Yoriko Fukase as her sole close friend. A pivotal moment occurs during a festival argument with Kaoru when Miyo encounters a mysterious anthropomorphic Mask Seller. He provides a magical Noh mask enabling her transformation into a blue-eyed white cat named Taro. As Taro, she nightly visits Hinode, receiving affection denied to her human self. This transformation offers escape from pain and symbolizes her yearning for unconditional acceptance, but increasingly blurs her identity; she confuses human and feline existences, prioritizing life as Taro to evade human struggles. Desperation intensifies after Hinode publicly ridicules her love letter and harshly rejects her confession. Devastated, Miyo relinquishes her human face to the Mask Seller to live permanently as a cat. Immediate regret follows as she comprehends the permanence of losing her humanity: communication and relationships. Trapped as Taro, she witnesses Kaoru's cat, Kinako, assume her human form and observes her family's frantic search, gaining an external perspective revealing their genuine care and love. This forces Miyo to acknowledge her self-deception; her family and Yoriko were never "scarecrows" but people who deeply valued her. This realization sparks her redemption. Pursuing the Mask Seller to supernatural Cat Island, she encounters other regretful transformed humans. With Kinako and Hinode—temporarily becoming half-cat using a mask—Miyo confronts the Mask Seller. Hinode apologizes for his rejection and confesses his feelings, strengthening her resolve. The experience culminates in Miyo reclaiming her human face after openly expressing her love for Hinode and accepting her need for human connection. Post-transformation, Miyo demonstrates significant growth: reconciling with Kaoru, repairing familial bonds, and adopting a more authentic, less performative approach to relationships. Her journey concludes with a mutual romantic commitment to Hinode and a newfound willingness to face life's challenges without escapism.