The story of Taketori Monogatari is widely believed to have taken place under Emperor Shomu during the Nara period, but there are many characters who should not have been there at the time, including some who were already dying at the time. It shows that it is an empty story.

In this volume, the traditional Tale of Taketori is modified to a certain extent, and although Heijokyo in the Nara period is also used as Kyoto, the ruler is replaced by Emperor Tenchi (Nakadai Brother) at the end of the Asuka period. Of course, Naba's opinion that these changes are actually not a big deal, and presumably you didn't click into this volume to review Japanese history.

In short, I want to say that you don't have to worry about the detailed rules, just watch the story.