He is Yakumo's uncle and father of Nao. He is kind of a father for Yakumo and lives in a Buddhist temple. In order to make Yakumo feel a little bit more comfortable he wears a red adherent lens. Also Isshin was the one who named Yakumo.

Haruka Ozawa's sophomore year is getting seriously scary. One of her friends is possessed, another has committed suicide and Haruka could be the next one to flunk the still-breathing test. Her only way out of this potentially lethal dead end? Yakumo Saito, an enigmatic student born with a mysterious red eye that allows him to see and communicate with the dead. But the deceased don't always desist and some killers are more than ready to kill again to keep dead men from telling any more tales. That doesn't stop Haruka's knack for digging up buried secrets, and there's even more evidence of bodies being exhumed by both Yakumo's police contact and an investigative journalist with a newly made corpse in her closet! Can this pair of anything but normal paranormal detectives solve the ultimate dead case files or will they end up in cold storage themselves? <br><br>
(Source: Sentai Filmworks)

Holds a 2nd Dan rank in Kendo. A veteran Japanese voice actor who has played characters in anime, drama CDs and video games. Apart from voice work, Toshihiko Seki sometimes does live-action drama stage work and is a member of 81 Produce.

__Non-anime roles:__
• Dottore (Genshin Impact)
• Chongyue (Arknights)

Isshin Saitou