"All the trials are a safety measure to see that no one with bad intentions walks inside the tree", the nice old lady explains for them. As she talks she will magically make the cup go back to its place and cleans Hijikata's lap.

As for the tree. "Things can be lost to the Darkness in various ways. They don't have to be completely taken by it to become lost."

The cat seems ready to spill the tea again, Hijikata.