“Oh, if you want to pee you can just do it out the front door,” my host Yuki says as he gives me an introductory tour of the house and points out the powder room — merely a pit with a long drop and an unconnected toilet pedestal covering the hole. I had just arrived with a friend named Henry on the island of Yakushima, which lies in the East China Sea about 190 km south of Kagoshima in Kyushu.