Nura

A supernatural saga of a 13-year-old by day, and a leader of a demon clan by night-straight from the pages of Weekly Shonen Jump!

While the day belongs to humans, the night belongs to yokai,
supernatural creatures that thrive on human fear. Caught between these
worlds is Rikuo Nura. He's three-quarters human, but his grandfather is
none other than Nurarihyon, the supreme commander of the Nura clan, a
powerful yokai consortium. So, Rikuo is an ordinary teenager three
quarters of the time, until his yokai blood awakens. Then Rikuo
transforms into the future leader of the Nura clan, leading a hundred
demons.

The battle against Nue heats up as Rikuo and members of the opposing clans move to Mt. Osore, a holy mountain where spirits of the dead are called into battle. Will a reforged Nenekirimaru, the renowned yokai-killing blade, work to defeat the legions of the undead?