From the introduction:
The Infernal Pagoda, ruled by the White Carnation Clan's tengu ninjas, stands deep within the Eight Blossom Forest, a haunted wood that few ever return from. Higher floors are home to increasingly more skilled ninjas. Kouki Asuka, the clan's leader, occupies the topmost floor. Asuka sits alone in deep meditation except when he entertains important guests from infernal realms. Various monsters, spirits, hungry ghosts, and visitors may be encountered within the Infernal Pagoda. Anyone skillful enough to ascend through the four lower stories to reach the highest floor is then free to sit upon the Jade Throne. For the brief time a mortal bears the throne's psychic energies, he commands power enough to grant himself a single wish. At least, that's what stories say, but those stories are lure enough.