It is not to say that the teacher didn't hurt the other students but it is clear the professor favoured garam because he has the exact same sound he wanted from a student. I personally can relate with the other students of heejae's because I had a teacher like that and because of him I started to hate my subject but along the way I met another teacher who was super kind and that reignited my interest in that subject
He is a doctor and doesn't even know what the clear fluid is and says he might have some sort of terminal disease
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The ML says in the later chapter that he feels"cheap sympathy" towards Hadi but surely wanted sympathy for his condition that his parents were killed due to political reasons.
How does a man so cruel, suddenly has his concious awakened that he repents the things he did. I don't believe for a second in this redemption arc.
