Taiki Yamamoto is the father and master of Naoki Yamamoto.
Synopsis[]
Taiki is first introduced throwing a kunai at Akisame Kōetsuji, only to have it blocked abruptly. It is later revealed that Ryōzanpaku intended to take Kenichi Shirahama to see Taiki's son Naoki, as they considered the two to be evenly matched in strength.
Later, Taiki poses as the demon in the cave who Naoki warns Kenichi about, and the two end up fighting the demon. Only shortly after is it revealed that Taiki intended the demon to be a test for the two disciples.

Taiki Yamamoto as the Tengu (demon)