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並不是所有的壁外之內故事都發生在壁外世界，例如這篇就是在主世界中日本一個不起眼的角落。
古時候，在這座大山中13歲結婚似乎是再正常不過的一件事。而成年禮，做為踏出大人台階的第一步，就是要讓女孩們與男人做愛，讓村裡的大家指導她們如何做好一個妻子。她們的天真與貞節都將結束在這個夏天。

Not all stories in "壁外の內" series take place in the world out of the wall. For example, this one takes place in an inconspicuous corner of Japan in the main world.
In ancient times, getting married at the age of 13 seemed to be a normal thing in this mountain. The coming-of-age ceremony, the first step towards adulthood, is for girls to have sex with men and let everyone in the village teach them how to be a good wife. Their innocence and chastity will end this summer.
*Unfortunately this novel is no version other than Chinese.