While undergoing medical treatment, young Sotaro Tsuji lies on a hospital rooftop and listens to a mysterious voice coming through a radio. When he opens his eyes, he finds himself on an unfamiliar island in Malaysia, where he meets Mimi, a woman known as an angel, and Daniel, the man who loves her. As Sotaro travels with them through the island's dreamlike landscape, he confronts himself and discovers unfamiliar emotions. Th is a fantasy prequel to Tobenai Tenshi (飛べない天使), set in George Town on Penang Island, Malaysia.