故事背景为存在「外」、「内」两个国家的世界，人类少女「汐华」与非人的异形「老师」共同生活，一段宛如绘本、童话与诗集的黑暗奇幻物语。<br>长篇动画附属于《外之国的少女》番外篇特装版。
遇播放卡顿或无法播放时，可切换线路播放
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