An adventure game based on the TV anime "Sound of the Sky". Members of the 1121st Platoon, a defense unit composed entirely of girls, are depicted struggling to perform at a music festival. Original characters that are not in the original also appear, and the story progresses with a little fan service happening. This work adopts a multi-view system, and the player can select the character who will be the "hero of the day" for each day and enjoy the scenario from each viewpoint. In addition, a parameter called "playing ability" is set for each character, and the playing ability goes up and down in daily events, and everyone's level can be confirmed "by ear" in daily practice.