Kishima Kouma

Eldest son of the Kishima. However, because the Kishima family itself has already died out, he is treated as the family head.
He was summoned by Tohno Makihisa to be his trump card in wiping out the Nanaya, and delivered results far beyond his expectations.
For Shiki, who subconsciously remembers the scenes of devastation from that time, Kouma has become a nigh insurmountable image of death.
With grip strength powerful enough crush enormous trees in his hands, inborn agility, and strange oni powers, he annihilates his enemies without mercy. Truly, he is an oni symbolic of scorching heat and burning flames.
Currently still alive.

A demon hybrid with Herculean strength. He is a descendent of the oni that once inhabited Japan, but whose numbers fell hand in hand with the expansion of civilization, until they finally went extinct.
With grip strength powerful enough crush enormous trees in his hands, inborn agility, and strange oni powers, he annihilates his enemies without mercy. Truly, he is an oni emblematic of scorching heat and burning flames.
Though the Kishima are one of the numerous Tohno branch families, they have long since fallen into decline. As far as Kouma was concerned, it would have been fine if he just quietly faded into obscurity in his forest den, letting the line die out for good. However, he was called out by Tohno Makihisa to be the Tohno’s trump card against the Nanaya, a role which he fulfilled perfectly. The Nanaya family was completely wiped out.
For Tohno Shiki, who subconsciously remembers the scenes of devastation from that time, Kouma has become a nigh insurmountable image of death.
Kouma himself, however, is a tranquil character, similar to a mountain ascetic aiming for enlightenment in order to find meaning in his own existence.