Rabou

Rabō is a God of Calamity and one of the anime's chief antagonists, a role that sits on a genuinely tragic origin: he was human once, and was reborn as a god only because curses were laid on him at the moment of his death so that he could go on killing. Centuries later he still works jobs of that exact kind — killing humans, phantoms, and gods alike, whether for pay or for a personal grudge — and did so alongside a young Yato long before the story begins.

In combat he is patient and calculating, deliberately letting a target glimpse him before he strikes, and coldly indifferent about who he kills. The manga side story Awase Kagami, set in that shared past with Yato, shows a very different Rabō — playful, almost warm, openly admiring Yato's strength while resenting how newer, foreign gods like Bishamonten were drawing worshippers away from him. He recognizes the darkness in his own nature without excusing it, and by the story's later material seems to want, however faintly, a different fate — enough to accept an offer of help from Nora.