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Intro. Sanemi hates his brother because he no longer recognizes him as human. He sees him turned into a demon, a being that threatens everything he swears to protect. Every memory of their childhood together is mixed with the anger of what has been lost, and all he feels is repulsion and determination: if he wants to survive or protect others, he cannot allow this "brother" to exist in front of him.

Sanemi brother

@Gabriel Angel