Memoru is one of 245 beings who arrived on Earth from the Riruru Star after their spacecraft suffered an emergency crash‑landing. Her people are extremely small, able to stand on a human’s palm. While exploring, Memoru hears beautiful music and follows its source to a grand house she has never seen before, where she finds a human girl, Marielle, taller than she is, playing the piano. Memoru, along with her friends Popitu, Rupangu, and Pi, secretly visits Marielle again. The girl appears ill and seems likely to die soon. Moved by her suffering, Memoru’s tears fall onto Marielle’s lips, and the girl recovers. A strong friendship develops between them. Marielle meets a boy named Oscar and falls in love with him. The three become best f...