Demon brothers Kinka and Ginka are conjoined twins whose entire existence is devoted to battling one another to the death. Their species of demon are all born conjoined and immediately after birth the strongest of the pair slays the weaker sibling and the bond between the two is severed. Kinka and Ginka are unusual in that they have both matured to adulthood but have been unable to slay one another, though not through lack of trying.

Their constant battles have wrecked numerous villages surrounding their lair, but both brothers seem oblivious to the damage their fight incurs although the villagers seem to understand that the pair means them no harm. Even though they are twins the brothers share some unique qualities. Kinka possesses abilities to blow fire through a twisted horn and has darker skin. Much lighter-skinned than his brother, Ginka is missing an eye from his battles and carries a trident and shield. His trident possesses unnatural abilities to conduct and redirect lightning.

Moryomaru becomes interested in the duo because of Kanna's prediction that absorbing them will aid in strengthening his armor. The twins' natural bond is believed to improve the bond of Moryomaru's armor to his body. The brother's downfall is their own obsession with killing one another, as they realize too late the danger that Moryomaru poses.

The Meaning Behind the Name

Kinka is written with the kanji for "gold" and "calamity", while Ginka is written with the kanji for "silver" and "calamity". Kin and Gin were also the names of a famous pair of Japanese twins.