Kamitoki no Resist

Kamitoki no Resist summary:

A red thread that entwines their fate thicker than blood, deeper than destiny. The Jinkishi, who keeps the demons (youki) sealed in the Capital has died and his magic has dissipated. Hayato has come from Tokyo to the Capital to claim the seat of the Jinkishi. However it's the blood of the Shihoudou family that inherits this power, and the possessor, Jin, has no interest or desire in the Jinkishi. As the story unfolds they are chained together by the red spell of fate.