Ayakashi

All his life he trained his techniques to perfection, reached mastery, yet never once before he fought in battle, never once he killed, never once he fulfilled his purpose, while he began to become old and his body to wilt.

He waited for the day to fulfill his purpose and desires. Therefore, he contracted with Dan Karuma.

Spoiler

And this day has truly come, when he fought to the death against the legions of oni, urged by and feared of great calamity, Nakiri Kuubou, holding pride in defending his country.

Spoiler

His true identity is the old man who has been met by Yoshiya when entering the dream world together with his friends for the first time.