In a quiet mountain village, the girl Watase Asuna (voiced by Hisako Kanemoto) often stands on the top of the mountain, using the mysterious ore left to her by her father as a diode, listening to the wonderful music from the outside world. On the way home from school, Asuna was attacked by a monster. At a critical moment, she was rescued by the handsome boy Shun (voiced by Irino Miyu), and pure friendship began to sprout between boys and girls. Asuna savored the sweetness of friendship, but she didn't know that Shun quietly passed away one day. The new male teacher Morisaki Ryuji (voiced by Inoue Kazuhiko) told the children the legend of the country of the dead, and Asuna realized that Shun was from another world, Yagotai. Morisaki's true identity belongs to a mysterious organization. He and Asuna both want to resurrect people in their hearts, so after twists and turns, they came to the legendary Yagotai with Shun's younger brother Kokoro. In this beautiful and desolate country, they embarked on a seemingly endless journey...