Hyabusa Jao needs a holiday. It’s winter, he’s tired, and his ribs are busted from his last job with the Good Men assassins. Jao’s boyfriend Hitori Masahiro wants to get out of Okatsu, as well, to rid himself of his opium dependency. Since money isn't an object with Masahiro, he can afford to book them into the exclusive Okina Kibou Onsen, a warm water spa in the mountains. Unfortunately Jao has been there before, for a job, and the place carries bad memories. But he can't tell Masahiro that, so they set off with family, friends, and servants in tow.When they arrive, the problems begin. First Jao runs into his least favorite person in the world, his ex-boss Kazematsuri. Then he thinks he sees the ghost of the man he killed at the onsen, and Masahiro becomes ill from opium withdrawal. Also, the two sons of the Daimyo of Okatsu, Kazuya and Daijiro, are there to hunt, or so they say. Jao tries to stay out of their way, but the two VIPs are disturbingly interested in both Jao and Masahiro, for different reasons.Then Kazuya, the younger and slightly nicer of the two brothers, is discovered torn almost to shreds by something big and catlike, an animal the like of which does not occur in the wilds around the onsen. While Kazuya is recovering, Jao is determined to find out what beast is sneaking around at night ... and keep it from killing anyone else.