[spoiler]Even if Shimako hasn’t a big role in Akane route. I believe she was essential to show the story of the Holy Woman. She allows to show a concrete example of Transcription, something which would remained unclear despite the explanations of Akane. The words are only words.
An other element that I appreciate is her weird relationship with Akane. In many other game, They would’ve been probably like sisters. But here, there is a distance and Akane doesn’t hesitate to send her to the death to protect the Key like the other summoners.
However, she regrets that Shimako doesn’t come to visit her and eventually take care her with Kotarou and does not take her to the choir. Leaving her a chance.
It allowed perhaps to show the evolution of Akane. Normally, their relationship would surely have been the same as Akane and Sakura Kashima because they are too similar. But Akane managed to show affection and to give her something before leaving. Not like Kashima to her death
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