Wait... 🤔 Maybe that's how the underground worked back then? When you drove off a yōkai, you didn't just chase them away. You banished them to Tartarus this place which was part of Hell. Effectively a prison, and they couldn't get back up to terrorize the populace.
Now, times have changed. When Hell moved on, I suppose that's when the sages make the deal with Satori when the new order of Gensōkyō was still in its infancy. Keep these lowlives and undersirables out of the community.
