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Tear Jerker: Code:Breaker
Ogami talking to the dying Hitomi:
Ogami: I'll never forget what you taught me...I'll never forget you.
Hitomi's life in general, especially as his story is expanded in the anime. He was conscripted at sixteen, watched his friends die horribly without the slightest recognition, but continued to fight for Eden for ten years. Then he found out about Code:End, attempted to convince the Prime Minister to let the Code:Breakers live real lives, and was attacked and driven out. He's forced to fight his charges whom he swore to protect, and then his power essentially eats him alive.