It can be considered a prequel to the same series, Touken Ranbu, which also explains the origins of those things that are somewhat unclear in the text.
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Tsukidai Munechika is a reverse-edged sword that is used by the gods. A girl, she woke up because of an accident. As an imitation sword of Mikazuki Munechika, she deliberately imitated it when she was born, but Toshi imitated her.
Yuedai Zongjin was helpless. When she decided to give up, she picked up the knife, got a honwan, and an inexplicable live broadcast.
Well, Yuedai Zongxuan can only stay alive. After all, she doesn't want the men who picked up the swords to have their swords broken because of her.
Then, I don't know what happened, but it turned into a storm.
(°ー°)(Wu Dai Zongjin is the original spirit and has spiritual power, so he cannot lower the branch spirit because the sword that is not recognized is not qualified)
Intention: Very light peace