[Machine Translation] In 1896, Junnosuke Sugiyama visited the detective agency started by Ryutaro Tsukinawa, an old acquaintance. The client, named Uozumi, told them that YASUNOJO URUSHIHARA, a bigwig who was rumored to be a shadowy confidant of Aritomo Yamagata, had been found dead with no head. What awaited them when they went to the mansion, Kuroryuso, where the crime took place, was a gruesome series of murders that was likened to an eerie warabi (a folk song sung in a Japanese folk song). This is a masterpiece of mystery novel that has captured the attention of the mystery world.