Part 5/8:
As time progresses, the students learn more about Koro Sensei’s past, which reveals he was once a human named Shinigami, subjected to cruel experiments resulting in his transformation into the creature they see today. This backstory introduces an emotional complexity to the character and alters the students’ perception of their mission.
Kayano, one of the students, emerges with personal motivations tied to her sister's tragic fate, which further complicates the narrative as tensions between revenge and compassion flare. The students are forced to grapple with their feelings towards Koro Sensei, who genuinely cares for their well-being, conflicting with their mission to kill him.
The Climax and Resolution