Yomotsuhegui: Shisha no Kuni no Kajitsu

A former police officer, Nawa Kanetsugu, was driven by vengeance after the murder of his wife and child. After serving time in prison, he begins a new pursuit of retribution and discovers he cannot be killed by ordinary wounds. A meeting with a mysterious girl reveals that he has consumed the fruit of Yomotsuhegui, a tree from the realm of the dead, granting him immortality and monstrous abilities. The girl, a deity of death, believes he may still possess a sense of justice and seeks his aid in battling other dangerous immortals. Nawa must decide whether to reclaim his humanity by helping others against supernatural threats or let his powers corrupt him into something monstrous.