双叶身边的每个人都期待她长大成人，而她却失去了保持心理平衡的能力。在她内心深处，她那颗童真的心依然存在，依然坚强。有一天，她闯入了异次元，一个光明消失、黑暗统治的世界。那里的人们就像穿着内裤的婴儿一样……
Everyone around Futaba expects her to grow up and become an adult, and she's lost the ability to keep herself mentally balanced. At the bottom of her heart, her childish self is still there, and still strong. One day she wanders into another dimension, a world where the light has been lost, and darkness rules. The people there exist as babies wearing only their underpants...
