They were approaching the truth with mystery remained---someone luckily detected mysterious messages, but accidentally died when about to reveal; someone who have weak personality, irresistibly went into "e;butterfly cemetery"e;; someone who owed sinful debts 18 years ago were destined to pay with life in this remote city... Among the original 19 people, only 10 survived.Suspicion continued to spread. Who would be the next oblation? Was the invisible enemy the real demon, or the hidden Trojan horse among them? When would truth come out, and when would fate reverse? When would the final trial arrive?