I'll second that for a while you're going to get a villain of the week vibe from the series and I looked at it that way too in the game.... until afterwards when it was explained that it's not all that simple.
EDIT: To get a little deeper into the plot, and I'll try not to spoiler anything, consider the issue of how to integrate tayutai into the modern world and how to foster a cooperative co-existence between humans and spirits. That's kind of the whole underlining issue running throughout the story.
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NYAA-CEPTION
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