High above the mountain, hidden above a thick layer of clouds, is the castle of Kokuunsai, an ootengu (great tengu) demon and the mountain's land lord. The castle is so high that humans cannot reach it unless they are carried by a karasutengu (烏天狗, crow tengu), one of the ootengu's many servants. Because Kokuunsai created much of the environment himself, it is especially sensitive to his moods, so the weather can change rapidly (and often violently) with little warning. In fact, portions of the castle are destroyed every time that it appears.