A fading summer, vanishing rural scenery, and the three long yet fleeting years of an adult schoolgirl role-play. In Tochigi, surrounded by mountains and rivers, another energetic summer passes in an instant as old country landscapes disappear to development. Amid that nostalgic setting, Maina discovers her unusual masochistic desires without knowing whether they are right or wrong, and gives herself over to languid sex. What did the ray of light from this secret final summer mean to her? Only her anus, left stretched wide open, knows the answer.