Tougen Anki

Shiki Ichinose lives recklessly without knowing anything about the ancient war still being fought between descendants of the Oni and descendants of Momotarou. When he is suddenly attacked, his adoptive father Tsuyoshi reveals the truth: Shiki carries Oni blood, while the man hunting them belongs to the lineage that has killed his kind for generations.

Tsuyoshi dies protecting him, violently awakening Shiki's Oni power and nearly causing the boy to lose himself. Oni instructor Naito Mudano then takes Shiki to Rasetsu Academy, where descendants of the Oni learn to control their abilities before those powers consume them. Shiki does not enter school seeking knowledge; he wants revenge. Yet understanding the war he inherited requires learning which parts of its history were told to him and which were written in the blood of the other side.