Shirotae will return. With that belief, Shouko does her best to understand the young man's multiple personality disorder. What are Shirotae's origins? How come his entire family are magic users? And how does one go to this alternate dimension, the Lake Nation?

It's the Heian Era in Ancient Japan, after numerous disasters and rebellions, The Emperor Suzaku believes Heaven has abandoned him and his advisors secretly consider ways to replace him, meanwhile, the sorcerers known as Onmyouji are dragged into a series of fights against demons summoned by mysterious curses. They will have to delve deep into conspiracies to discover the true nature of these cases.

Caught in the conflict between the Mikogami Family and the Kuroe Family, twin sisters Maiko and Shouko will need to use the full extent of their supernatural abilities and investigational skills to uncover the truth behind a bizarre demonic ritual disguised as a murder in Wakayama Prefecture.