The spirit world is divided. Its inhabitants, strange creatures called yokai, have chosen sides, and the two factions are on the brink of all-out war. A bird-like yokai who wields some serious firepower faces off against a club-wielding demon. Mariko Yashida finds herself right in the middle of it. No matter which side she chooses, there will be consequences not only for the spirit world, but for the human world too.