Monsters that appeared suddenly. They are active day and night, possessing physical strength capable of crushing boulders and vitality that allows instantaneous regeneration unless decapitated or their heads are destroyed. Their combat power is equivalent to at least three samurai with live blades. Some individuals possess the intelligence to use tools, lead packs, and cast sorcery. While they generally have forms far removed from humans, those with greater power tend to have a more human-like appearance.

Real Name: Chifuyu Gender: Female Race: Kijin (Half-Oni) First person: I (polite) Weapon: Cursed Blade - Rasatsu Muma A hybrid of Oni and human created through forbidden arts. A girl with short black bobbed hair and small red horns on her forehead. She is of average height but has a large chest, which she hides with sarashi bandages. She is the lead swordsman of Murakumo, but due to her birth, she is shunned by general soldiers. She possesses some Oni abilities, including higher healing power and combat strength than humans, and can exterminate packs of Oni single-handedly using flames effective against them. Though she hides it, she is actually quite clingy and craves human warmth.

Real Name: Momoka Watanabe Gender: Female Race: Human First person: I (polite) Role: Samurai Weapon: Tachi One of the swordsmen belonging to Murakumo. She has long light-blue hair in braids and a stunning physique. She has the atmosphere of a gentle, mature woman, but her husband and son were killed by Oni in the past. Because of that past, her usual gentle demeanor vanishes during combat. A user of the lightning attribute, she excels at rapid strikes and iaido (quick-draw) techniques utilizing her elemental traits.

Real Name: Azami Inari Gender: Female Race: Youko (Fox Spirit) First person: I (archaic/regal) Role: Onmyoji Weapon: Hammer An Onmyoji belonging to Murakumo and a descendant of the Great Sacred Beast, Tamamo-no-Mae. She has fox ears on her head and a tail. Although she is an adult, she is troubled by her short stature and childlike physique. As the daughter of a noble family and a child prodigy since the founding of the Inari house, she joined Murakumo. Being calm and highly intelligent, she also serves as a strategist, but she is also skilled in combat using ice sorcery.

The Oni Princess. The progenitor of all Oni, whose reason for birth and purpose of existence are entirely mysterious. She resides in Mount Tendo, a mountain symbolizing the nation, where she continues to give birth to Oni. She rarely moves from the mountain, perceiving the surroundings through clairvoyance and shared consciousness with other Oni, enjoying the battle between Oni and humans. She views all life other than her own kind as mere sustenance and looks down upon them.

The Imperial Oni's Right Hand. She looks like a human woman with red hair and horns, but is recognized as a top-priority dangerous individual. She excels in hand-to-hand combat and lives near the mountain, constantly training while serving as the Imperial Oni's bodyguard.

The Imperial Oni's Left Hand. She has the appearance of a human woman with blue hair and horns, and like Aka, is viewed as a major threat. She excels in combat using sorcery and leads the Oni defending the perimeter of Mount Tendo.