Plot: One night, Masaomi explains to Riku about what Toujinshi and Shikigami are, and why the Ten-ryuu and the Chi-ryuu are currently fighting. It seems that the Chi-ryuu is interested in opening the Fukumaden Kimon, a gate that leads to demons and a power that could destroy the world, and the Ten-ryuu are trying to keep the Fukumaden Kimon closed