Great youkai of boundaries. It was just that that time happened to be now. It was just that it came in Hakurei Reimu's generation—that was all. —Gensokyo accepted everything. Even ends. She knew that nothing could be done. That was why—Reimu didn't do anything. Because she knew that it would be useless no matter what she did, she wanted to spend her time peacefully until it ended. Until the last moment, she wanted to be 'as she always was.' Together with the youkai who supported the Hakurei family for generations and loved Gensokyo more than anyone. But,
that youkai was—trying to preserve the free hentai border.
Even though she probably knew that it was futile, even though the end would only come a little later if she did that—Yakumo Yukari, for some reason, was trying to maintain the border. No matter how powerful a youkai Yakumo Yukari was, she was facing a whole world. It was close to a miracle that she was even able to hold it. But still, the end didn't stop hentai. The 'borders' became vague, and as if to show that, Yakmno Yukari became worn out. She couldn't watch. At least in the end—in the short time before the end, she wanted to spend her time with her. But still, Reinm did not stop her. Because that was what she wanted to do. Not stopping her, she just watched. The sight of
Gensokyo ending. While feeling the time she had left pass. That was why
Reimu was angry at the human from the outside who came into Gensokyo by opening up the boundary.
Not as the system called the Hakurei shrine maiden who managed the border, but as the human called Reimu who budded inside it. For the small, small feeling she had for the yonkai, who knew more about the truth of the world and loved Gensokyo, since she met her.