"An invitation for a Druid to visit your land. The next guest in your inn will be a Druid. While he stays at your inn, he permanently increases the characteristics of the pets caught on your land by 10%."

Shouldn't that "permanently" be a "temporarily"? Or does the effect last even after he is gone?

The pets caught while the Druid was in your Inn have permanent 10% characteristics bonus, otherwise the benefit from this guest would be doubtful.